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Analyzing the spatiotemporal evolution and driving forces of gross ecosystem product in the upper reaches of the Chaobai River Basin

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Frontiers of Environmental Science & Engineering 2024年第8期18卷 117-132页

作者： Jiacheng Li Qi han Liqiu Zhang Li feng Guihuan Liu Beijing Key Laboratory for Source Control Technology of Water Pollution College of Environmental Science and EngineeringBeijing Forestry UniversityBeijing 100083China Engineering Research Center for Water Pollution Source Control&Eco-remediation College of Environmental Science and EngineeringBeijing Forestry UniversityBeijing 100083China Center of Eco-compensation Chinese Academy of Environmental PlanningMinistry of Ecology of EnvironmentBeijing 100041China

The Chaobai River Basin,which is a crucial ecological barrier and primary water source area within the Beijing-Tianjin-Hebei region,possesses substantial ecological *** gross ecosystem product(GEP)in the Chaobai River Basin is a reflection of ecosystem conditions and quantifies nature’s contributions to humanity,which provides a basis for basin ecosystem service management and *** study investigated the spatiotemporal evolution of GEP in the upper Chaobai River Basin and explored the driving factors influencing GEP spatial *** patterns from 2005 to 2020 were analyzed,and GEP was calculated for 2005,2010,2015,and *** driving factors influencing GEP spatial differentiation were identified using the optimal parameter-based geographical detector(OPGD)*** key findings are as follows:(1)From 2005 to 2020,the main ecosystem types were forest,grassland,and *** areas experienced significant changes,and conversions mainly occurred among urban,water,grassland and agricultural ecosystems.(2)Temporally,the GEP in the basin increased from 2005 to 2020,with regulation services *** the county(district)scale,GEP exhibited a north-west-high and south-east-low pattern,showing spatial differences between per-unit-area GEP and county(district)GEP,while the spatial variations in per capita GEP and county(district)GEP were similar.(3)Differences in the spatial distribution of GEP were influenced by regional natural geographical and socioeconomic *** these factors,gross domestic product,population density,and land-use degree density contributed *** among different driving forces noticeably impacted GEP spatial *** findings underscore the necessity of incorporating factors such as population density and the intensity of land-use development into ecosystem management decision-making processes in the upper reaches of the Chaobai River *** policies

关键词： Ecosystem pattern Gross ecosystem product(GEP) Spatiotemporal evolution Optimal parameter-based geographical detector(OPGD) Chaobai River Basin

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Built-in electric field induced S-scheme g-C_(3)N_(4)homojunction for efficient photocatalytic hydrogen evolution:Interfacial engineering and morphology control

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Nano Research 2024年第6期17卷 4961-4970页

作者： Yongpan Gu Yike Li Haoqiang feng Yanan han Zhongjun Li College of Chemistry Zhengzhou UniversityZhengzhou 450001China

S-scheme possesses superior redox capabilities compared with the II-scheme,providing an effective method to solve the innate defects of g-C_(3)N_(4)(CN).In this study,S-doped g-C_(3)N_(4)/g-C_(3)N_(4)(SCN-tm/CN)S-scheme homojunction was constructed by rationally integrating morphology control with interfacial engineering to enhance the photocatalytic hydrogen evolution ***-situ Kelvin probe force microscopy(KPFM)confirms the transport of photo-generated electrons from CN to *** functional theory(DFT)calculations reveal that the generation of a built-in electric field between SCN and CN enables the carrier separation to be more efficient and *** transient absorption spectrum(fs-TAS)indicates prolonged lifetimes of SCN-tm/CN_(3)(τ1:9.7,τ2:110,andτ3:1343.5 ps)in comparison to those of CN(τ1:4.86,τ2:55.2,andτ3:927 ps),signifying that the construction of homojunction promotes the separation and transport of electron hole pairs,thus favoring the photocatalytic *** visible light irradiation,the optimized SCN-tm/CN_(3)exhibits excellent photocatalytic activity with the hydrogen evolution rate of 5407.3μmol·g^(−1)·h^(−1),which is 20.4 times higher than that of CN(265.7μmol·g^(−1)·h^(−1)).Moreover,the homojunction also displays an apparent quantum efficiency of 26.8%at 435 nm as well as ultra-long and ultra-stable cycle *** work offers a new strategy to construct highly efficient photocatalysts based on the metal-free conjugated polymeric CN for realizing solar energy conversion.

关键词： homojunction built-in electric field morphology control interfacial engineering carrier separation

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Geochemistry and origins of hydrogen-containing natural gases in deep Songliao Basin,China:Insights from continental scientific drilling

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Petroleum Science 2024年第2期21卷 741-751页

作者： Shuang-Biao han Chao-han Xiang Xin Du Lin-feng Xie Jie Huang Cheng-Shan Wang College of Geoscience and Surveying Engineering China University of Mining and TechnologyBeijing100083China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesBeijing100083China

The different reservoirs in deep Songliao Basin have non-homogeneous lithologies and include multiple layers with a high content of hydrogen *** gas composition and stable isotope characteristics vary significantly,but the origin analysis of different gas types has previously been *** on the geochemical parameters of gas samples from different depths and the analysis of geological settings,this research covers the diverse origins of natural gas in different *** gas components are mainly methane with a small amount of C_(2+),and non-hydrocarbon gases,including nitrogen(N_(2)),hydrogen(H_(2)),carbon dioxide(CO_(2)),and helium(He).At greater depth,the carbon isotope of methane becomes heavier,and the hydrogen isotope points to a lacustrine sedimentary *** increasing depth,the origins of N_(2)and CO_(2)change gradually from a mixture of organic and inorganic to *** origins of hydrogen gas are complex and include organic sources,water radiolysis,water-rock(Fe^(2+)-containing minerals)reactions,and *** shales of Denglouku and Shahezi Formations,as source rocks,provide the premise for generation and occurrence of organic ***,the deep faults and fluid activities in Basement Formation control the generation and migration of mantle-derived *** discovery of a high content of H_(2)in study area not only reveals the organic and inorganic association of natural-gas generation,but also provides a scientific basis for the exploration of deep hydrogen-rich gas.

关键词： Gas compositions Stable isotopes Gas origins Hydrogen gas Songliao Basin

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Innovative construction of macroporous–mesoporous structured spherical alumina and its hydrothermal stability

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Particuology 2024年第7期90卷 429-435页

作者： Yufan Mo Chunli Li Huiyu Li Wei han He Wen Yinghong han Chunxia Che Yongjun feng State Key Laboratory of Chemical Resource Engineering Beijing Engineering Center for Hierarchical CatalystsCollege of ChemistryBeijing University of Chemical TechnologyBeijing100029China Lanzhou Petrochemical Research Center Petrochemical Research InstitutePetroChinaLanzhou730060China

The pore structure of spherical alumina supports is closely related to the dispersion of catalytically active components and the diffusion of *** excellent pore structure under strict reaction conditions is of utmost *** this work,sphericalγ-Al_(2)O_(3)support with a bimodal pore structure,composed of macropores and mesopores,was successfully synthesized using dodecane as the pore-forming agent through the oil–ammonia column-shaping *** morphology and internal pore structure of the alumina were found to be influenced by the amount of surfactant added and ultrasound treatment ***,when concentration of surfactant was 4‰and ultrasound voltage of 20 V was applied,the resultingγ-Al_(2)O_(3)-4‰-20 displayed a highly concentrated distribution of macropores with an average pore size of 100 nm,resulting in an impressive porosity of 69.21%.In contrast,the untreated sample ofγ-Al_(2)O_(3)-0-0 only exhibited a mesoporous distribution with a porosity of 54.03%.Moreover,after being subjected to a hydrothermal treatment in a high temperature(600°C)and high humidity(water vapor)environment for 120 h,theγ-Al_(2)O_(3)-4‰-20 sample maintained a high BET specific surface area of 170.9 m^(2)g^(−1)and mercury intrusion porosimetry specific surface area of 263.3 m^(2)g^(−1).

关键词： Spherical alumina supports Pore-forming agent Oil-ammonia column shaping method Hydrothermal treatment Hydrothermal stability

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Primordial black hole mass functions as a probe of cosmic origin

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Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 164-171页

作者： Yi-Fu Cai Chengfeng Tang Geyu Mo Sheng-feng Yan Chao Chen xiao-han Ma Bo Wang Wentao Luo Damien A.Easson Antonino Marcianò Deep Space Exploration Laboratory/School of Physical Sciences University of Science and Technology of ChinaHefei 230026China CAS Key Laboratory for Researches in Galaxies and Cosmology/Department of Astronomy School of Astronomy and Space ScienceUniversity of Science and Technology of ChinaHefei 230026China Istituto Nazionale di Fisica Nucleare(INFN) Sezione di MilanoMilano 20146Italy DiSAT Universitàdegli Studi dell'InsubriaComo 22100Italy Jockey Club Institute for Advanced Study The Hong Kong University of Science and TechnologyHong KongChina Department of Physics Arizona State UniversityTempe 85287-1504USA Department of Physics&Center for Field Theory and Particle Physics Fudan UniversityShanghai 200433China Laboratori Nazionali di Frascati INFN Via Enrico Fermi 541 Frascati(Roma)00044Italy INFN sezione Roma Tor Vergata Rome I-00133Italy School of Physics University of Electronic Science and Technology of ChinaChengdu11731China

We discuss a novel window to probe the origin of our universe via the mass functions of primordial black holes(PBHs).The mass functions of PBHs are simply estimated using the conventional Press-Schechter formalism for two paradigms of cosmic origin,including inflationaryΛCDM and bounce *** standard inflationaryΛCDM model cannot generate an appreciable number of massive PBHs;however,non-trivial inflation models with blue-tilted power spectra at small scales and matter bounce cosmology provide formation mechanisms for heavy PBHs,which in turn,may seed the observed supermassive black holes(SMBHs).By fitting the SMBH mass functions at high redshift(z~6)derived from Sloan Digital Sky Survey(SDSS)and Canada-France High-z Quasar Survey(CFHQS)quasars,for two paradigms of cosmic origin,we derive constraints on the PBH density fraction fPBHat z~6 and the characteristic mass M_(★),with the prior assumption that all SMBHs stem from *** demonstrate that this newly proposed procedure,relying on astronomical measurements that utilize deep-field surveys of SMBHs at high redshift,can be used to constrain models of cosmic ***,although not the main focus of this paper,we evolve the mass function from z~6 to z~0 through an assumption of 3×10^(8)-year Eddington’s accretion,and give a rough estimation of fPBHat z~0.

关键词： origin cosmic massive

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Multi-scale hash encoding based neural geometry representation

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Computational Visual Media 2024年第3期10卷 453-470页

作者： Zhi Deng Haoyao xiao Yining Lang Hao feng Juyong Zhang School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026China Alibaba Artificial Intelligence Governance Laboratory Alibaba GroupHangzhou 310017China

Recently, neural implicit function-basedrepresentation has attracted more and more attention,and has been widely used to represent surfacesusing differentiable neural networks. However, surfacereconstruction from point clouds or multi-view imagesusing existing neural geometry representations stillsuffer from slow computation and poor accuracy. Toalleviate these issues, we propose a multi-scale hashencoding-based neural geometry representation whicheffectively and efficiently represents the surface asa signed distance field. Our novel neural networkstructure carefully combines low-frequency Fourierposition encoding with multi-scale hash encoding. Theinitialization of the geometry network and geometryfeatures of the rendering module are accordinglyredesigned. Our experiments demonstrate that theproposed representation is at least 10 times faster forreconstructing point clouds with millions of *** also significantly improves speed and accuracyof multi-view reconstruction. Our code and modelsare available at https://***/Dengzhi-USTC/Neural-Geometry-Reconstruction.

关键词： neural geometry representation hash encoding point cloud reconstruction multi-view reconstruction

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Recent Advances in the Synthesis of Zeolites from Solid Wastes

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Chemical Research in Chinese Universities 2024年第4期40卷 646-656页

作者： LIU Pei WU Qinming CHEN Zhenghai xiao feng-Shou Key Laboratory of Biomass Chemical Engineering of Ministry of Education and College of Chemical and Biological Engineering Zhejiang UniversityHangzhou310028P.R.China Zhejiang Provincial Innovation Center of Green Petrochemical Technology Ningbo315048P.R.China Kente Catalysts Inc. Xianju317300P.R.China

With the rapid development of industrialization,it is inevitable to produce solid wastes in the fields of energy petrochemical ***,the storage and utilization of these solid wastes have become a considerable *** to the main element composition of these solid wastes including silicon and aluminum,it has attracted extensive attention for synthesizing *** review summarized the properties of major solid wastes including coal fly ash,coal gangue,spent fluid catalytic cracking(FCC)catalyst,lithium slag,bauxite residue,and waste ***,the preparation of LTA,FAU,ZSM-5,SSZ-13,Beta,and MOR zeolites from these solid wastes were ***,the current challenges and perspectives were discussed.

关键词： Solid waste Zeolite Utilization Sustainable route Application

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Dynamic simulation analysis of molten salt reactor-coupled air-steam combined cycle power generation system

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Nuclear Science and Techniques 2024年第2期35卷 222-233页

作者： Jing-Lei Huang Guo-Bin Jia Li-feng han Wen-Qian Liu Li Huang Zheng-han Yang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

A nonlinear dynamic simulation model based on coordinated control of speed and flow rate for the molten salt reactor and combined cycle systems is proposed here to ensure the coordination and stability between the molten salt reactor and power *** model considers the impact of thermal properties of fluid variation on accuracy and has been validated with *** study reveals the capability of the control system to compensate for anomalous situations and maintain shaft stability in the event of perturbations occurring in high-temperature molten salt tank outlet ***,the control system’s impact on the system’s dynamic characteristics under molten salt disturbance is also *** results reveal that after the disturbance occurs,the controlled system benefits from the action of the control,and the overshoot and disturbance amplitude are positively correlated,while the system power and frequency eventually return to the initial *** simulation model provides a basis for utilizing molten salt reactors for power generation and maintaining grid stability.

关键词： Molten salt reactor Combined cycle Dynamic characteristic Control

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Microstructure and Mechanical Behavior of Mg-Based Bimetal Plates with High Formability Sleeve by Co-extrusion

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 499-512页

作者： Yue-Hui Dang Sheng-Lin Liu xiao-Lei Ai xiao-Wei feng Bo feng Zhuo Tian Ying-Fei Lin Huan-Tao Chen Kai-Hong Zheng School of Materials Science and Engineering Chang’an UniversityShaanxi 710064China Guangdong Key Laboratory of Metal Toughening Technology and Application Institute of New MaterialsGuangdong Academy of SciencesGuangzhou 510650China

In this study,microstructure and mechanical behavior of two types of Mg-based bimetal plates with a high formability sleeve were systematically studied,with a great emphasis on the effect of the interface characteristic and the sleeve fraction on the plasticity of composite *** rule of mixtures(ROM)for elongation was also *** results show that when there is no or thin diffusion layer with thickness of about 3μm,Mg-based bimetal plates have a good plasticity with elongation of about 19-24%,and the ROM predicted elongations are very close to the experimental *** contrast,with a diffusion layer about 95-155μm thick,Mg-based bimetal plates exhibit a poor plasticity with elongation of about 11-17%,and the experimental elongations largely deviate from the ROM *** plasticity of Mg-based bimetal plates increases with increasing sleeve *** study provides new insights on the plastic deformation of Mg-based bimetal composites with a high formability sleeve.

关键词： Mg-based composites Co-extrusion Microstructure Mechanical behavior Plastic deformation

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Development and application of novel high‐efficiency composite ultrafine cement grouts for roadway in fractured surrounding rocks

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Deep Underground Science and Engineering 2024年第1期3卷 53-69页

作者： Maolin Tian Shaojie Chen Lijun han Hongtian xiao Shandong Key Laboratory of Civil Engineering Disaster Prevention and Mitigation Shandong University of Science and TechnologyQingdaoChina College of Civil Engineering and Architecture Shandong University of Science and TechnologyQingdaoChina College of Energy and Mining Engineering Shandong University of Science and TechnologyQingdaoChina State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhouChina

The fractured surrounding rocks of roadways pose major challenges to safe *** has often been used to reinforce the surrounding rocks to mitigate the safety risks associated with fractured *** aim of this study is to develop highly efficient composite ultrafine cement(CUC)grouts to reinforce the roadway in fractured surrounding *** materials used are ultrafine cement(UC),ultrafine fly ash(UF),ultrafine slag(US),and additives(superplasticizer[SUP],aluminate ultrafine expansion agent[AUA],gypsum,and retarder).The fluidity,bleeding,shrinkage,setting time,chemical composition,microstructure,degree of hydration,and mechanical property of grouting materials were evaluated in this ***,a suitable and effective CUC grout mixture was used to reinforce the roadway in the fractured surrounding *** results have shown that the addition of UF and US reduces the plastic viscosity of CUC,and the best fluidity can be obtained by adding 40%UF and 10%*** UC and UF particles are small,the pozzolanic effect of UF promotes the hydration reaction,which is conductive to the stability of CUC *** addition,fine particles of UC,UF,and US can effectively fill the pores,while the volumetric expansion of AUA and gypsum decreases the pores and thus affects the microstructure of the solidified *** compressive test results have shown that the addition of specific amounts of UF and US can ameliorate the mechanical properties of CUC ***,the CUC22‐8 grout was used to reinforce the No.20322 belt *** results of numerical simulation and field monitoring have indicated that grouting can efficaciously reinforce the surrounding rock of the *** this research,high‐performance CUC grouts were developed for surrounding rock reinforcement of underground engineering by utilizing UC and some additives.

关键词： broken surrounding rock composite ultrafine cement(CUC)grouts grouting material grouting performance grouting reinforcement

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