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Effects of Terracing and Agroforestry on Soil and Water Loss in Hilly Areas of the Sichuan Basin, china

Journal of Mountain Science 2008年第3期5卷 241-248页

作者： J.H. ZHANg Z.A. SU g.c. liu Key Laboratory of Mountain Hazards and Earth Surface Processes Chinese Academy of Sciences 610041 China Institute of Mountain Hazards and Environment Chinese Academy of Sciences ＆Ministry of Water Conservancy Chengdu 610041 China The graduate School of the chinese Academy of Sciences Beijing 100049 China

Soil erosion in hilly areas of the Sichuan Basin is a serious concern over sustainable crop production and sound ecosystem. A 3-year experiment was conducted using the method of runoff plots to examine the effects of terracing and agroforestry in farmland systems on soil and water conservation of slope fields in the hilly areas in Jianyang.c.unty, Sichuan Province, Southwestern china. A power function (Y = aXb) can statistically describe the relationship between water runoff (Y) and rainfall (X). The regression equation for the treatment of sloping terraces with crops (Plot 2) is remarkably different from that for the treatment of sloping terraces with grasses and trees (Plot 1) and the conventional up- and down-slope crop system (Plot 3) regarding equation coefficients, while regression equations are similar between Plot 1 and Plot 3. Water runoff amount and runoff coefficient of slope fields increased by 21.5～41.0 % and 27.5～69.7 % respectively, compared to those of sloping terraces, suggesting that terracing notably reduced the water runoff in the field. In the case of sloping terraces, lower amount of water runoff was observed on sloping terraces with crops than on sloping terraces with grasses and trees. Sediment yields on the slope fields in the normal year of rainfall distribution were notably higher (34.41～331.67 % and 37.06～403.44 % for Plot 1 and Plot 2, respectively) than those on sloping terraces, implying that terracing also plays a significant role in the reduction in soil erosion. It is suggested that terracing with crops is significantly effective for soil and water conservation in cultivatedfarmland, while the conventional practice of up- and down- slope cultivation creates high rates of water runoff and soil sediment transport. Terracing with grasses and fruit trees shows a less reduction in water runoff than terracing with crops, which was observed in the 3-year experiments.

关键词： Agroforestry sediment transport runoff sloping terrace soil and water conservation

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Edge supercurrent in Josephson junctions based on topolog.c.l materials

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Science china(Physics,Mechanics & Astronomy) 2025年第2期68卷 1-12页

作者： Junjie Qi chui-Zhen chen Juntao Song Jie liu Ke He Qing-Feng Sun X.c.Xie Beijing Academy of Quantum Information Sciences Beijing 100193China School of Physical Science and Technology Soochow UniversitySuzhou 215006China Institute for Advanced Study Soochow UniversitySuzhou 215006China college of Physics and Hebei Advanced Thin Films Laboratory Hebei Normal UniversityShijiazhuang 050024China School of Physics Xi’an Jiaotong UniversityMinistry of Education Key Laboratory for Non-Equilibrium Synthesis and Modulation of Condensed MatterXi’an 710049China State Key Laboratory of Low Dimensional Quantum Physics Department of PhysicsTsinghua UniversityBeijing 100084China Frontier Science center for Quantum Information Beijing 100084China Hefei National Laboratory Hefei 230088China International center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China Interdisciplinary center for Theoretical Physics and Information Sciences Fudan UniversityShanghai 200433China

The interplay between novel topolog.c.l states and superconductivity has garnered substantial interest due to its potential for topolog.c.l quantum *** Josephson effect serves as a useful probe for edge superconductivity in these hybrid topolog.c.l *** Josephson junctions based on topolog.c.l materials,supercurrents exhibit unique quantum interference patterns,including the conventional Fraunhofer oscillations,theΦ_(0)-periodic oscillation,and the 2Φ_(0)-periodic oscillation in response to the external magnetic field(Φ_(0)=h/2e is the flux quantum,h the Planck constant,and e the electron charge).These interference patterns stem from varied Andreev reflection mechanisms and the associated current density *** review seeks to comprehensively examine the theoretical and experimental advancements in understanding the quantum interference patterns of edge supercurrents in Josephson junctions based on quantum spin Hall,quantum Hall,and quantum anomalous Hall systems.

关键词： quantum Hall effect quantum spin Hall effect quantum anomalous Hall effect Josephson junction edge supercurrent Andreev reflection

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Relational characteristics and dynamics between high-tech firms in the Pearl River Delta and the empowerment for technolog.c.l innovation by Hong Kong

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Journal of geographical Sciences 2025年第2期35卷 382-408页

作者： XU Jili Anthony g.O.YEH george c.S.LIN liu Xingjian YANg Fan Fiona LUO Zixin guangzhou Institute of geography Guangdong Academy of Sciences Department of Urban Planning and Design The University of Hong Kong Department of geography The University of Hong Kong School of geography and Planning Sun Yat-Sen University

The perfection of the cross-border regional innovation system of the Pearl River Delta(PRD) and Hong Kong remarkably underpins the construction of the guangdong-Hong Kong-Macao greater Bay Area(gBA) towards an international technolog.c.l innovation *** paper focuses on the relational characteristics of the usage of technolog.c.l innovation functions and elements, including labor force, technology, and producer services from Hong Kong by high-technology firms in the PRD, and probes into the influencing factors by integrating the objective perspective on the impact of firm-level socioeconomic attributes and subjective perspective on the open interpretations on the reasons by using or not using technolog.c.l innovation functions and elements from Hong Kong by various stakeholders in high-technology domains in the PRD. Key research findings are fourfold. First, Hong Kong's technolog.c.l innovation functions primarily ride on its institutional advantages under the “One country, Two Systems” framework to empower high-technology firms in the PRD by expanding their international market, international business operation, and financing, but cross-border investment and entrepreneurship has retrieved to a relatively marginalized position. The degree of supply-demand relations of producer services is the highest, followed by labor force and ***, Hong Kong-invested, large-sized, and long-standing high-technology firms in the PRD are more inclined to use technolog.c.l innovation elements from Hong Kong, while domestic,small-and-medium-sized, and start-up high-technology firms in the PRD are in turn, gradually unhooked from the supply of technolog.c.l innovation elements from Hong Kong. Third, Hong Kong enjoys both advantages and disadvantages in supplying labor forces, technologies, and producer services to high-technology firms in the PRD, with advantages in competitiveness,international linkages and visions, and disadvantages in high cost, lack of more profoun

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Anomalous open orbits in Hofstadter spectrum of chern insulator

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Science china(Physics,Mechanics & Astronomy) 2025年第3期Mechanics & Astronomy) .卷 143-148页

作者： Haijiao Ji Peng Zhou Noah F.Q.Yuan Hua Jiang Haiwen liu X.c.Xie center for Advanced Quantum Studies Department of Physics Beijing Normal University Tsung-Dao Lee Institute Shanghai Jiao Tong University Department of Mathematics UC Berkeley Institute for Nanoelectronic Devices and Quantum computing Fudan University International center for Quantum Materials School of Physics Peking University Hefei National Laboratory

The nontrivial band topology of chern insulator can enrich the content of its Hofstadter butterfly spectra, which is closely related to recent experiments in twisted bilayer graphene and cold atom systems. We investigate the Hofstadter spectrum for various models of chern insulators under a rational flux φ0/q, here φ0=h/e and q being an integer. We find the number of splitting subbands is |q-c| with c denoting the chern number of parent band. Importantly, anomalous open-orbital subbands with chern numbers q-1 and-q-1 emerge unexpectedly, which are beyond the parameter window（-q/2, q/2） of the Diophantine equation studied by Thouless-Kohmoto-Nightingale-den Nijs [Phys. Rev. Lett. 49, 405（1982）]. The emergence of anomalous open orbits can be traced by analyzing the evolution of the Hofstadter spectrum, identifying as a new type of topolog.c.l phase transition. These novel findings not only pinpoint the peculiar Hofstadter spectrum of chern insulator, but also provide routes to study exotic characteristics beyond the Landau level physics.

关键词： Hofstadter spectrum topolog.c.l phase transition open orbit

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Rational modulation of fluorophosphate cathode by anionic groups to reduce the polarization behavior for fast-charging sodium-ion batteries

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Journal of Energy chemistry 2025年第1期100卷 509-521页

作者： Xinyuan Wang Fan Zhang Xingyu Zhou Qian Wang.c.angyu liu Yangyang liu Hui Wang Xiaojie liu Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry&Materials ScienceNorthwest UniversityXi’an 710127ShaanxiChina

Na_(3)V_(2)(PO_(4))_(2)O_(2)F (VP) is recognized as a promising.c.thode material for sodium-ion batteries due to its stable structural framework and high specific *** functional theory (DFT) and finite element simulations show that incorporating SO_(4)^(2-)into VP decreases its band gap,lowers the migration energy barrier,and ensures a uniform Na+concentration gradient and stress distribution during.c.arge and discharge ***,the average Na+diffusion coefficient of Na_(3)V_(2)(PO_(4))_(1.95)(SO_(4))_(0.05)O_(2)F(VPS-1) is roughly double that of VP,leading to enhanced rate capability (80 c,75.5 mAh g^(-1)) and cycling stability (111.0 mAh g^(-1)capacity after 1000 cycles at 10 c current density) for ***-1 exhibits outstanding fast-charging.c.pabilities,achieving an 80%state of charge in just 8.1 *** assembled VPS-1//SbSn/NPc full cell demonstrated stable cycling over 200 cycles at a high 5 c current,maintaining an average coulombic efficiency of 95.35%.

关键词： Anionic group modulation Polarization behavior Fast-charging Sodium-ion battery Fluorophosphate cathode

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construction of iron manganese metal-organic framework-derived manganese ferrite/carbon-modified graphene composites toward broadband and efficient electromagnetic dissipation

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International Journal of Minerals,Metallurgy and Materials 2025年第3期32卷 546-555页

作者： Baohua liu Shuai liu Zaigang Luo Ruiwen Shu School of chemical and Blasting Engineering Anhui Province Key Laboratory of Specialty PolymersAnhui University of Science and TechnologyHuainan 232001China Joint National-Local Engineering Research centre for Safe and Precise coal Mining Anhui University of Science and TechnologyHuainan 232001China

The preparation of carbon-based electromagnetic wave(EMW)absorbers possessing thin matching thickness,wide absorption bandwidth,strong absorption intensity,and low filling ratio remains a huge ***-organic frameworks(MOFs)are ideal self-sacrificing templates for the construction of carbon-based EMW *** this work,bimetallic FeMn-MOF-derived MnFe_(2)O_(4)/c/graphene composites were fabricated via a two-step route of solvothermal reaction and the following pyrolysis *** results re-veal the evolution of the microscopic morphology of carbon skeletons from loofah-like to octahedral and then to polyhedron and pomegran-ate after the adjustment of the Fe^(3+)to Mn^(2+)molar ***,at the Fe^(3+)to Mn^(2+)molar ratio of 2:1,the obtained MnFe_(2)O_(4)/c/graphene composite exhibited the highest EMW absorption ***,a minimum reflection loss of-72.7 dB and a max-imum effective absorption bandwidth of 5.1 gHz were achieved at a low filling ratio of 10wt%.In addition,the possible EMW absorp-tion mechanism of MnFe_(2)O_(4)/c/graphene composites was ***,the results of this work will contribute to the construction of broadband and efficient carbon-based EMW absorbers derived from MOFs.

关键词： metal-organic frameworks graphene magnetic composites morphology regulation electromagnetic dissipation

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Exhumation and Preservation of the Yangchuling Porphyry W-Mo Deposit in the Jiangnan Tungsten Ore Belt,South china:Insights from(U-Th)/He and Fission Track Dating

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Journal of Earth Science 2025年第1期36卷 46-56页

作者： Yue Sun Ying Wang Jianzhang Pang Samuel c.Boone Minting Wu chongjian Shao Wei liu Jiangxi Provincial Key Laboratory of genesis and Prospect for Strateg.c.Minerals School of Earth ScienceEast China University of TechnologyNanchang330013China Institute of geology china Earthquake Administration Beijing100029China School of geography Earth and Atmospheric Sciences The University of MelbourneMelbourneVIC3010Australia Department of Earth Sciences The University of AdelaideAdelaideSA5005Australia Jiangxi Duchang JinDing Tungsten cO. Ltd.Jiujiang332611China

The Yangchuling porphyry W-Mo deposit(YPWD),located in the Jiangnan porphyryskarn tungsten ore belt,is one of the most important and large-scale porphyry W-Mo deposits in South *** previous zircon U-Pb and molybdenite Re-Os data suggest that Yangchuling WMo ore bodies formed almost simultaneously with granodiorite and monzogranitic porphyry at~150–144 Ma,their post emplacement history remains poorly understood,making their preservation status at depth *** this paper,new zircon and apatite(U-Th)/He and apatite fission track(ZHe,AHe and AFT,respectively)data of one hornfels and five intrusive rocks from a 1000-meter borehole are ***,together with new inverse thermal history models and previous geochronolog.c.l data,help elucidate the post-diagenetic exhumation history and preservation status of the Yangchuling porphyry W-Mo *** general,ZHe and AHe ages decrease gradually from the near surface downwards and have relatively little intra-sample variation,ranging from 133 to 73Ma and 67 to 25 Ma,*** four granodiorites yield similar AFT ages that range from 63 to 55 Ma with mean track lengths varying from 12.2±0.7 to 12.6±0.5μ*** history modelling indicates that the Yangchuling ore district experienced slow,monotonic cooling since the ***-depth relationships are interpreted as recording~3.7±0.8 km of cretaceous-recent exhumation in response to regional extension throughout South china thought to have been driven by subduction retreat of the Paleo-Pacific *** of estimated net exhumation and previous metallogenic depth of~4–5 km suggests that W-Mo ore bodies could still exist at depths of up to~1.3±0.8 km relative to Earth surface in the YPWD *** of the YPWD is attributed to the limited amount of regional denudation during the Late cretaceous and cenozoic.

关键词： (U-Th)/He fission track ore preservation thermochronology Yangchuling porphyry W-Mo deposit

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Long-duration aqueous Zn-ion batteries achieved by dual-salt highly-concentrated electrolyte with low water activity

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Journal of Energy chemistry 2025年第2期101卷 778-785页

作者： Lvzhang Jiang Lingbo Yao gege Wang.c.ang liu Xiaowei chi Yu liu Shanghai Institute of ceramics Chinese Academy of Sciences University of chinese Academy of Sciences

Aqueous Zn-ion batteries have attracted much attention due to their unique high safety and low-cost ***,their practical applications are at a slow pace due to their short cycle life,which fundamentally results from the instability of the positive/negative electrode interface in the traditional dilute aqueous electrolytes with high water *** highly concentrated electrolyte（HcE）has been considered as an effective *** previous studies of single salt-based HcE（SSHcE）,herein,a new dual-salt HcE（15 m Zncl2+10 m NH4NH2SO3DS-HcE） was proposed for the first ***-HcE was proven to simultaneously possess higher conductivity than traditional dilute electrolytes and ultralow water activity of SS-HcE by the regulation of dual high-concentration salts on the solvation structure,which renders the Zn‖Zn symmetric cell the record-long.c.cling life of 2200 h compared with those with SS-HcE（30 m Zncl2,300 h） and other reported ***,the Zn‖NH4V4O10full cell with DS-HcE demonstrated impressed rate capability within a wide-range current densities from 0.1 to 10 A ***,at the high current density of 5 A g-1,the full cell shows almost100% capacity retention after 4000 cycles,which indicates the promising future of the DS-HcE system for long-duration aqueous Zn-ion batteries.

关键词： Ammonium vanadate Aqueous zinc battery cycling stability Electrolyte

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Functional ternary salt construction enabling an in-situ Li3N/LiF-enriched interface for ultra-stable all-solid-state lithium metal batteries

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Journal of Energy chemistry 2025年第2期101卷 68-75页

作者： Hong-Yan liu Xin-Yu liu Nan Zhang Peng-Fei Wang Zong-Lin liu Jie Shu Ting-Feng Yi School of Materials Science and Engineering Northeastern University Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province School of Resources and Materials Northeastern University at Qinhuangdao Faculty of Materials Science and chemical Engineering and Key Laboratory of Photoelectric Detection Materials and Devices of Zhejiang Province Ningbo University

Poly（ethylene oxide）-based polymer all-solid-state lithium metal batteries（ASSLBs） have received widespread attention due to their low cost,good process ability,and high energy ***,the growth of Li dendrites within polymer solid-state electrolytes damages the reversibility of Li anodes and still impedes their widespread *** efficient strategy is to construct a superior solid electrolyte ***,a stable interface enriched with Li3N and LiF is in-situ formed between Li anode and a terna ry salt *** terna ry salt electrolyte is innovatively designed by introducing lithium bis（trifluoromethane sulfonyl）imide（LiTFSI）,lithium bis（fluorosulfonyl）imide（LiFSI）,and LiNO3to poly（ethylene oxide） *** characterization indicates that LiNO3and LiFSI contribute to forming a Li3N-LiF-enriched interface and meanwhile LiTFSI ensures excellent ***,among various Li compound components,Li3N has high ionic conductivity,which is beneficial for reducing overpotential,while LiF has high interfacial energy which can enhance nucleation energy and suppress the formation of Li *** experimental results show that ASSLBs coupled with LiFePO4cathode display extremely excellent cycle stability approximately 2200 cycles at 2 c,with a final and corresponding discharge specific capacity of 96.7 mA h g-1. Additionally,a schematic illustration of the working mechanism for the Li3N-LiF interface is proposed.

关键词： All-solid-state lithium metal batteries In-situ SEI Lithium dendrite PEO (LiTFSI) Solid electrolyte

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Hybrid ecophysiolog.c.l growth model for deciduous Populus tomentosa plantation in northern china

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Forest Ecosystems 2025年第01期 112-120页

作者： Serajis Salekin Mark Bloomberg Benye Xi Jinqiang liu Yang liu Doudou Li Euan g.Mason Scion Research (New Zealand Forest Research Institute Ltd.) New Zealand School of Forestry University of Canterbury State Key Laboratory of Efficient Production of Forest Resources Beijing Forestry University Key Laboratory for Silviculture and Forest Ecosystem Research in Arid-and Semi-Arid Region of National Forestry and grassland Administration Beijing Forestry University Key Laboratory for Silviculture and conservation of Ministry of Education Beijing Forestry University Institute of Medicinal Plant Development Chinese Academy of Medical Sciences Peking Union Medical College

Short rotation plantation forestry（SRF） is being widely adopted to increase wood production, in order to meet global demand for wood products. However, to ensure maximum gains from SRF, optimised management regimes need to be established by integrating robust predictions and an understanding of mechanisms underlying tree growth. Hybrid ecophysiolog.c.l models, such as potentially useable light sum equation（PULSE） models, are useful tools requiring minimal input data that meet the requirements of SRF. PULSE models have been tested and calibrated for different evergreen conifers and broadleaves at both juvenile and mature stages of tree growth with coarse soil and climate data. Therefore, it is prudent to question: can adding detailed soil and climatic data reduce errors in this type of model? In addition, PULSE techniques have not been used to model deciduous species, which are a challenge for ecophysiolog.c.l models due to their phenology. This study developed a PULSE model for a clonal Populus tomentosa plantation in northern china using detailed edaphic and climatic data. The results showed high precision and low bias in height（m） and basal area(m2·ha-1) predictions. While detailed edaphoclimatic data produce highly precise predictions and a good mechanistic understanding, the study suggested that local climatic data could also be employed. The study showed that PULSE modelling in combination with coarse level of edaphic and local climate data resulted in reasonably precise tree growth prediction and minimal bias.

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