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Responses of soil stoichiometry and soil enzyme activities in the different distance around opencast coal mine of the Hulun Buir Grassland of China

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International Journal of Coal Science & Technology 2024年第1期11卷 221-231页

作者： Yinli bi Nan Guo Yanxu Zhang Xianglei Li Ziheng Song State Key Laboratory for Fine Exploration and Intelligent Development of Coal Resources China University of Mining and Technology(Beijing)Beijing100083China Institute of Ecological Environment Restoration in Mine Areas of West China Xi’an University of Science and TechnologyXi’an710054China

The objectives of this study were to explore the changes in soil stoichiometry and enzyme activities at different distances from an opencast coal mine in the Hulun Buir Grassland of China. Four transects were established on north and east sides of the opencast coal mining area, and samples were collected at 50 m, 550 m, and 1550 m from the pit on each transect. Control samples were collected from a grassland station 8 km from the opencast coal mining area that was not disturbed by mining. Four replicate soil samples were collected at each point on the four transects. Soil physicochemical properties and enzyme activities were determined, and correlations between soil properties and stoichiometric ratios and enzyme activities were explored using redundancy analysis. The increase in distance from mining did not significantly affect soil properties, although soil urease activity was significantly lower than that of the control area. Soil properties 1550 m from the mine pit were similar to those at the grassland control. In addition, soil total nitrogen had the greatest effect on soil stoichiometry, and soil total potassium had the greatest effect on soil enzyme activities. Coal dust from opencast mining might be the main factor affecting soil stoichiometry and enzyme activities. The results of this study provide direction for the next step in studying the influence of mining areas on soil properties and processes.

关键词： Opencast coal mine Soil stoichiometry Soil enzyme activities Distance Grassland

Influence of rare earth oxides on microstructure and mechanical properties of nickel-based superalloys fabricated by high energy beam processing:A review

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Journal of Rare Earths 2024年第9期42卷 1629-1645,I0001页

作者： Lianjie bi Hua Yan Peilei Zhang Haichuan Shi Zhiyuan Li Ruidi Li School of Materials Science and Engineering Shanghai University of Engineering ScienceShanghai201620China College of Agricultural Science and Engineering Hohai UniversityNanjing211100China Department of Mechanics and Maritime Science Chalmers University of TechnologyGothenburSE41296Sweden State Key Laboratory of Powder Metallurgy Central South UniversityChangsha410083China

In this paper,the effects of rare earth oxides on the micro structure and mechanical properties of nickelbased superalloys prepared by high-energy beam processing technology were critically *** focus is on the optimal amount of rare earth oxides that can produce ideal *** attention was paid to their main strengthening mechanisms,including solid solution strengthening mainly in the form of solid solution dissolved in the nickel-based alloy and improving the microstructure of the alloy by grain refinement or fine grain strengthening produced by homogenizing the distribution phase.Y_(2)O_(3),La_(2)O_(3) and CeO_(2) rare earth oxides can also improve the fluidity of the alloy molten pool and reduce the segregation of alloying *** advantages can significantly improve the mechanical properties of the ***,this paper outlines the future research directions of rare earth oxides,aiming to expand their application potential.

关键词： Rare earths High energy beam Nickel-based superalloys Microstructure Mechanical properties

Analysis of optical axis deviation caused by structural stiffness in equatorial telescopes

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Astronomical Techniques and Instruments 2024年第4期1卷 203-210页

作者： Haibo Li Runfu peng Chenggang Shu Yong bi Shaoming Hu School of Mathematics and Science Shanghai Normal UniversityShanghai 200234China Research and Development Center CAS Nanjing Astronomical Instruments Co.LTDNanjing 210042China Shandong Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment School of Space Science and PhysicsInstitute of Space SciencesShandong UniversityWeihaiWeihai 264209China

The impact of structural stiffness on optical axis deviation poses a significant challenge in the design of equatorial telescope structures.A comprehensive analysis during the design process can reduce the reliance of a telescope on advanced control technologies,thereby improving its economic *** full-system finite element analyses are reliable,they are encumbered by significant time requirements and limitations in covering all possible telescope ***,we propose an efficient and comprehensive analytical method to evaluate the optical axis deviation of equatorial telescopes across a full range of *** address the challenge of ensuring that the analysis covers all possible positions of an equatorial telescope,based on a model from SiTian project,we analyze the optical axis deviations caused by the fork arm at 25 different angles and then use fitting methods to obtain results for all *** on the analysis results of the optical axis deviation caused by the stiffness of the optical tube in the horizontal position,we derive the results for the tube at any position using geometric ***,we calculate the coupling factors and combine these ***,we identify six discrete feature points to reflect possible telescope orientations and conduct comprehensive finite element *** results are in alignment with those acquired through a comprehensive computational approach.

关键词： Astronomical instrumentation Telescopes Equatorial mounts Multivariate analysis

Structural Characteristics and Influencing Factors of Carbon Emission Spatial Association Network:A Case Study of Yangtze River Delta City Cluster,China

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Chinese Geographical Science 2024年第4期34卷 689-705页

作者： bi Xi SUN Renjin HU Dongou SHI Hongling ZHANG Han School of Economics and Management China University of Petroleum(Beijing)Beijing 102249China China Petroleum Planning&Engineering Institute Beijing 100083China

City cluster is an effective platform for encouraging regionally coordinated *** reduction of carbon emissions within city cluster via the spatial association network between cities can help coordinate the regional carbon emission management,realize sustainable development,and assist China in achieving the carbon peaking and carbon neutrality *** paper applies the improved gravity model and social network analysis(SNA)to the study of spatial correlation of carbon emissions in city clusters and analyzes the structural characteristics of the spatial correlation network of carbon emissions in the Yangtze River Delta(YRD)city cluster in China and its influencing *** results demonstrate that:1)the spatial association of carbon emissions in the YRD city cluster exhibits a typical and complex multi-threaded network *** network association number and density show an upward trend,indicating closer spatial association between cities,but their values remain generally ***,the network hierarchy and network efficiency show a downward trend but remain high.2)The spatial association network of carbon emissions in the YRD city cluster shows an obvious‘core-edge’distribution *** network is centered around Shanghai,Suzhou and Wuxi,all of which play the role of‘bridges’,while cities such as Zhoushan,Ma'anshan,Tongling and other cities characterized by the remote location,single transportation mode or lower economic level are positioned at the edge of the network.3)Geographic proximity,varying levels of economic development,different industrial structures,degrees of urbanization,levels of technological innovation,energy intensities and environmental regulation are important influencing factors on the spatial association of within the YRD city ***,policy implications are provided from four aspects:government macro-control and market mechanism guidance,structural characteristics of the‘core-edge’network,reconfigura

关键词： carbon emission spatial association network social network analysis(SNA) quadratic assignment procedure(QAP)model Yangtze River Delta city cluster China

A modified 3D mean strain energy density criterion for predicting shale mixed-mode Ⅰ/Ⅲ fracture toughness

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2411-2428页

作者： Kun Zheng Chaolin Wang Yu Zhao Jing bi Haifeng Liu College of Civil Engineering Guizhou UniversityGuiyang550025China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China

The fracture toughness of rocks is a critical fracturing parameter in geo-energy exploitation playing a significant role in fracture mechanics and hydraulic *** edge-notched disk bending(ENDB)specimens are employed to measure the entire range of mixed-modeⅠ/Ⅲfracture toughness of Longmaxi *** theoretically interpret the fracture mechanisms,this research first introduces the detailed derivations of three established fracture *** distinguishing the volumetric and distortional strain energy densities,an improved three-dimensional mean strain energy density(MSED)criterion is *** the critical volumetric to distortional MSED ratio decreases,the transition from tensiondominated fracture to shear-dominated fracture is *** results indicate that both peak load and applied energy increase significantly with the transition from pure mode I(i.e.,tension)to pure modeⅢ(i.e.,torsion or tearing)since mode-Ⅲcracking happens in a twisted manner and mode-Ⅰcracking occurs in a coplanar *** macroscopic fracture signatures are consistent with those of triaxial hydraulic *** average ratio of pure mode-Ⅲfracture toughness to pure mode-Ⅰfracture toughness is 0.68,indicating that the obtained mode-Ⅲfracture resistance for a tensionbased loading system is apparent rather than *** to the three mainstream fracture criteria,the present fracture criterion exhibits greater competitiveness and can successfully evaluate and predict mixed-modeⅠ/Ⅲfracture toughness of distinct materials and loading methods.

关键词： Longmaxi shale Hydraulic fracturing Fracture mechanisms Fracture criteria Mixed-modeⅠ/Ⅲfracture toughness Edge-notched disk bending

Trade-offs between the accumulation of cuticular wax and jasmonic acid-mediated herbivory resistance in maize

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Journal of Integrative Plant biology 2024年第1期66卷 143-159页

作者： Jiong Liu Lu Li Zhilong Xiong Christelle AMRobert Baozhu Li Shan He Wenjie Chen Jiasheng bi Guanqing Zhai Siyi Guo Hui Zhang jieping Li Shutang Zhou Xi Zhang Chun‐peng Song School of Life Sciences Henan UniversityKaifeng 475004China State Key Laboratory of Crop Stress Adaptation and Improvement Henan UniversityKaifeng 475004China State Key Laboratory of Cotton bio‐Breeding and Integrated Utilization Henan UniversityKaifeng 475004China Sanya Institute of Henan University Sanya 572025China Institute of Plant Sciences University of BernBern 3013Switzerland

Plants have evolved complex physical and chemical defense systems that allow them to withstand herbivory *** of a complex mixture of very-long-chain fatty acids(VLCFAs)and their derivatives,cuticular wax constitutes the first physical line of defense against ***,we report the function of Glossy 8(ZmGL8),which encodes a 3-ketoacyl reductase belonging to the fatty acid elongase complex,in orchestrating wax production and jasmonic acid(JA)-mediated defenses against herbivores in maize(Zea mays).The mutation of GL8 enhanced chemical defenses by activating the JA-dependent *** observed a trade-off between wax accumulation and JA levels across maize glossy mutants and 24 globally collected maize inbred *** addition,we demonstrated that mutants defective in cuticular wax biosynthesis in Arabidopsis thaliana and maize exhibit enhanced chemical *** transcriptomic and lipidomic analyses indicated that the gl8 mutant confers chemical resistance to herbivores by remodeling VLCFA-related lipid metabolism and subsequent JA biosynthesis and *** results suggest that VLCFA-related lipid metabolism has a critical role in regulating the trade-offs between cuticular wax and JA-mediated chemical defenses.

关键词： cuticular wax fall armyworm herbivore resistance jasmonic acid maize plant-herbivore interactions

Formation mechanism of Fe-based amorphous powders produced by spark erosion

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Journal of Materials Science & Technology 2024年第3期170卷 33-46页

作者： Chekai Liu Ran Li Jiazi bi Ding Ma Xiaobin Liu Tao Zhang School of Materials Science and Engineering Key Laboratory of Aerospace Materials and Performance(Ministry of Education)Beihang UniversityBeijing 100191China

Spark erosion is a convenient,flexible,and low-cost method to quickly produce fine powders of metals,alloys,and semiconductors in size ranging from nearly a hundred micrometers to submicrometer by repetitive spark *** to the complexity of the powder-forming journey,normally accompanied by high temperature,high pressure,decomposition,diffusion and rapid quenching caused by discharge plasma,the mechanisms of powder formation and possible contaminant infiltration are still controversial,posing a significant challenge to control particle size and chemical composition of the powder produced by this *** this study,Fe-based amorphous powders in different particle-size distributions with high sphericity were fabricated by spark erosion under different discharge-energy *** max-imum particle size of the resultant powders can be correlated with discharge parameters,crater depth,and crater radius,respectively.A multi-ring-breakup model is proposed to reveal the particle-size distribution of the powder formed from the electrode melt under a single-pulse ***,a dielectric-element infiltration model is provided to quantitatively evaluate the infiltration mass ratio of the contaminant elements,stemming from the decomposed products of dielectric liquid,in the resultant powder with different particle *** models verified through the experimental data are significant for the development of high-performance fine Fe-based amorphous powder with controlled particle size and chemical composition.

关键词： Amorphous alloy Particle Spark erosion Infiltration Modeling

Plasmon bi in-situ anchored on biOCl nanosheets assembled microspheres towards optimized photothermal-photocatalytic performance

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Chinese Chemical Letters 2024年第2期35卷 469-476页

作者： Dongxue Song Mingxia Li Fan Yang Menghan Yu Zhenzi Li jie Chen Xiaoshuang Zhang Wei Zhou School of Chemistry and Materials Science Key Laboratory of Functional Inorganic Material ChemistryMinistry of Education of the People's Republic of ChinaHeilongjiang UniversityHarbin 150080China Shandong Provincial Key Laboratory of Molecular Engineering School of Chemistry and Chemical EngineeringQilu University of Technology (Shandong Academy of Sciences)Ji'nan 250353China

Interface engineering is of great importance to improve the photocatalytic ***,in-situ formation plasmon bi/biOCl nanosheets assembled heterojunction microspheres are fabricated via facile reductive solvothermal *** aldehyde group in the DMF structure is used to exert the weak reducing property of the solvent and thus strip out the metal bi in *** metal bi is anchored on surface of biOCl firmly due to in-situ formation engineered interface,which could realize efficient charge transfer *** resultant bi/biOCl heterojunctions assemblies with narrow bandgap of 3.05 eV and mesoporous structure extend the photoresponse to visible light region and could provide sufficient surface active *** visible-light-driven photocatalytic degradation of high-toxic norfloxacin for bi/biOCl heterojunctions is up to 95.5%within 20 min,representing several times that of pristine biOCl nanosheets and the physical *** is attributed to the in-situ formation of bi/biOCl heterojunctions and surface plasmon resonance(SPR)effect of plasmon bi promoting charge transfer,and the obvious photothermal effect promoting the photocatalytic reaction,which are verified by experimental and density functional theory(DFT)*** strategy provides ideal perspectives for fabricating metal/semiconductor heterojunctions photocatalysts with high-performance.

关键词： Photocatalysis biOCl Heterojunction Plasmon bi Mesoporous structure

A Review of Privacy and Security of Edge Computing in Smart Healthcare Systems: Issues, Challenges, and Research Directions

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Tsinghua Science and Technology 2024年第4期29卷 1152-1180页

作者： Ahmad Alzu’bi Ala’a Alomar Shahed Alkhaza’leh Abdelrahman Abuarqoub Mohammad Hammoudeh Department of Computer Science Jordan University of Science and TechnologyIrbid 22110Jordan Cardiff School of Technologies Cardiff Metropolitan UniversityCardiff CF52YBUK Department of Information and Computer Science King Fahd University of Petroleum and MineralsDhahran 31261Kingdom of Saudi Arabia

The healthcare industry is rapidly adapting to new computing environments and technologies. With academics increasingly committed to developing and enhancing healthcare solutions that combine the Internet of Things (IoT) and edge computing, there is a greater need than ever to adequately monitor the data being acquired, shared, processed, and stored. The growth of cloud, IoT, and edge computing models presents severe data privacy concerns, especially in the healthcare sector. However, rigorous research to develop appropriate data privacy solutions in the healthcare sector is still lacking. This paper discusses the current state of privacy-preservation solutions in IoT and edge healthcare applications. It identifies the common strategies often used to include privacy by the intelligent edges and technologies in healthcare systems. Furthermore, the study addresses the technical complexity, efficacy, and sustainability limits of these methods. The study also highlights the privacy issues and current research directions that have driven the IoT and edge healthcare solutions, with which more insightful future applications are encouraged.

关键词： edge computing fog computing data privacy healthcare systems intelligent edges