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Comparative Analysis of Fractional Vegetation Cover Estimation Based on Multi-sensor Data in a Semi-arid Sandy Area

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Chinese Geographical Science 2019年第1期29卷 166-180页

作者： liU Qiuyu ZHANG Tinglong li yizhe li Ying BU Chongfeng ZHANG Qingfeng College of Natural Resources and Environment Northwest A&F University Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources

The estimation of fractional vegetation cover(FVC) is important for identifying and monitoring desertification, especially in arid and semiarid regions. By using regression and pixel dichotomy models, we present the comparison of Sentinel-2A(S2) multispectral instrument(MSI) and Landsat 8(L8) operational land imager(Oli) data regarding the retrieval of FVC in a semi-arid sandy area(Mu Us Sandland, China, in August 2016). A combination of unmanned aerial vehicle(UAV) high-spatial-resolution images and field plots were used to produce verified data. Based on a normalized difference vegetation index(NDVI) regression model, the results showed that, compared with that of L8, the coefficient of determination(R2) of S2 increased by 26.0%, and the root mean square error(RMSE) and the sum of absolute error(SAE) decreased by 3.0% and 11.4%, respectively. For the ratio vegetation index(RVI) regression model, compared with that of L8, the R2 of S2 increased by 26.0%, and the RMSE and SAE decreased by 8.0% and 20.0%, respectively. When the pixel dichotomy model was used, compared with that of L8, the RMSE of S2 decreased by 21.3%, and the SAE decreased by 26.9%. Overall, S2 performed better than L8 in terms of FVC inversion. Additionally, in this paper, we develop a verified scheme based on UAV data in combination with the object-based classification method. This scheme is feasible and sufficiently robust for building relationships between field data and inversion results from satellite data. Further, the synergy of multi-source sensors(especially UAVs and satellites) is a potential effective way to estimate and evaluate regional ecological environmental parameters(FVC).

关键词： fractional vegetation cover (FVC) Sentinel-2A (S2) unmanned aerial vehicle (UAV)image pixel dichotomy model regression model

High throughput screening of single atomic catalysts with optimized local structures for the electrochemical oxygen reduction by machine learning

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Journal of Energy Chemistry 2023年第6期81卷 349-357,I0009页

作者： Hao Sun yizhe li liyao Gao Mengyao Chang Xiangrong Jin Boyuan li Qingzhen Xu Wen liu Mingyue Zhou Xiaoming Sun State Key Laboratory of Chemical Resource Engineering College of ChemistryBeijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

Single atomic catalysts(SACs),especially metal-nitrogen doped carbon(M-NC)catalysts,have been extensively explored for the electrochemical oxygen reduction reaction(ORR),owing to their high activity and atomic utilization ***,there is still a lack of systematic screening and optimization of local structures surrounding active centers of SACs for ORR as the local coordination has an essential impact on their electronic structures and catalytic ***,we systematic study the ORR catalytic performance of M-NC SACs with different central metals and environmental atoms in the first and second coordination sphere by using density functional theory(DFT)calculation and machine learning(ML).The geometric and electronic informed overpotential model(GEIOM)based on random forest algorithm showed the highest accuracy,and its R^(2) and root mean square errors(RMSE)were 0.96 and 0.21,respectively.30 potential high-performance catalysts were screened out by GEIOM,and the RMSE of the predicted result was only 0.12 *** work not only helps us fast screen high-performance catalysts,but also provides a low-cost way to improve the accuracy of ML models.

关键词： Single atomic catalysts Coordination sphere High throughput screening Machine learning Oxygen reduction reaction

Spatially-resolved relaxor to ferroelectric phase switching in 0.93Na_(1/2)Bi_(1/2)TiO_(3)-0.07BaTiO_(3) ceramics

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Journal of Materiomics 2022年第5期8卷 976-981页

作者： Xi Shi Udo Eckstein yizhe li David Hall Neamul H.Khansur Department of Materials Science and Engineering Friedrich-Alexander-University Erlangen-Nürnberg(FAU)ErlangenGermany Department of Materials University of ManchesterManchesterUK

In situ,spatially-resolved synchrotron X-ray diffraction was utilized to investigate the electric fieldinduced heterogenous phase transformation of nonergodic relaxor 0.93Na^(1/2)Bi^(1/2)TiO_(3)-0.07BaTiO_(3) ceramics.A Cu electrode was coated on one surface of a rectangular sample by aerosol deposition(AD),while a Pt layer was deposited on the opposite surface by sputter *** is anticipated that a different stress state and/or domain morphology should occur on the AD deposited Cu electrode side due to the particle impact-consolidation deposition *** an electric field,different sample regions,i.e.,AD,Middle,and Sputter sides,showed systematic changes in the relaxor to ferroelectric phase transition *** particular,mostgrains transformed at a sub-coercive field of 0.8 kV/mm,while the majority of thegrains only appeared to undergo transitions at a higher field(2.4 kV/mm).Also,the tetragonal phase became the dominant structure at higher field ***,bothandgrains undergo phase switching at lower fields in the region close to the AD-processed *** study indicates that the AD process-induced stress can facilitate the electric field-induced relaxor to ferroelectric phase transition,i.e.,the AD Cu side showed more significant lattice strain and domain texture than the sputter Pt side.

关键词： Relaxor ferroelectric Synchrotron X-ray diffraction Phase transformation

Acceptor doping and actuation mechanisms in Sr-doped BiFeO_(3)-BaTiO_(3)ceramics

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Journal of Materiomics 2024年第1期10卷 57-69页

作者： Ziqi Yang yizhe li Bing Wang Juncheng Pan Annette K.Kleppe David A.Hall Department of Materials University of ManchesterM139PLManchesterUK Diamond light Source Ltd. Harwell Science and Innovation CampusOX110DEDidcotUK

BiFeO_(3)-BaTiO_(3)(BF-BT)ceramics are important multiferroic materials,which are attracting significant attention for potential applications in high temperature lead-free piezoelectric *** the present study,the effects of Sr^(2+)as an acceptor dopant for Bi^(3+),in the range from 0 to 1.0%(in mole),on the structure and ferroelectric/piezoelectric properties of 0.7BiFeO_(3)-0.3BaTiO_(3)ceramics were *** use of a post-sintering Ar annealing process was found to be an effective approach to reduce electrical conductivity induced by the presence of electron holes associated with reoxidation during cooling.A low Sr dopant concentration(0.3%,in mole)yielded enhanced ferroelectric(P_(max)∼0.37 C/m^(2),P_(r)∼0.30 C/m^(2))and piezoelectric(d_(33)∼178 pC/N,k_(p)∼0.27)properties,whereas higher levels led to chemically heterogeneous core-shell structures and secondary phases with an associated decline in *** electric field-induced strain of the Sr-doped BF-BT ceramics was investigated using a combination of digital image correlation macroscopic strain measurements and in-situ synchrotron X-ray *** of the intrinsic(lattice strain)and extrinsic(domain switching)contributions to the electric field induced strain indicated that the intrinsic contribution dominated during the poling process.

关键词： Bismuth ferrite-barium titanate Acceptor doping Electroceramics Piezoelectricity In-situ X-ray diffraction

Analysis of the Status and Rational Allocation of Water Resources in China in View of the New Era

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Journal of World Architecture 2023年第6期7卷 89-94页

作者： yizhe li Northwest Normal University Lanzhou 730070Gansu ProvinceChina

This paper examines the current status of water resource management and conservation in China,along with strategies to address the water resource *** the current situation,the paper highlights issues such as incomplete legal mechanisms,limited environmental awareness among enterprises,and insufficient government *** ad-dress these challenges,the paper proposes a series of strategies,including improving the ecological environment,enhanc-ing production techniques,strengthening management systems,rationalizing water resource allocation,and implementing water-saving measures in both industrial and agricultural *** strategies serve to achieve sustainable water resource management,reduce water pollution,and effectively tackle the pressing water resource issues faced in China currently.

关键词： Water resources Ecological environment Water security,protection,and utilization

Comprehensive Analysis of Indoor Formaldehyde Removal Techniques:Exploring Physical,Chemical,and Biological Methods

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Journal of Architectural Research and Development 2024年第1期8卷 8-13页

作者： yizhe li Northwest Normal University Lanzhou 730070Gansu ProvinceChina

This research focuses on the evaluation of diverse approaches for removing formaldehyde from indoor environments,which is a significant concern for indoor air *** study systematically examines physical,chemical,and biological methods to ascertain their effectiveness in formaldehyde *** methods,including air circulation and adsorption,particularly with activated carbon and molecular sieves,are assessed for their efficiency in various concentration *** methods,such as photocatalytic oxidation using titanium dioxide and plasma technology,are analyzed for their ability to decompose formaldehyde into non-toxic ***,biological methods involving plant purification and microbial transformation are explored for their eco-friendly and sustainable removal *** paper concludes that while each method has its merits,a combined approach may offer the most effective solution for reducing indoor formaldehyde *** study underscores the need for further research to integrate these methods in a practical,cost-effective,and environmentally sustainable manner,highlighting their potential to improve indoor air quality significantly.

关键词： Indoor air quality Formaldehyde removal Photocatalytic oxidation Activated carbon Biological purification

Advancements and Applications of Polyurethane Curing Technology in Railway Track Bed Construction in China

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Journal of World Architecture 2024年第1期8卷 12-17页

作者： yizhe li Northwest Normal University Lanzhou 730070Gansu ProvinceChina

This paper examines the application of polyurethane curing technology in the construction of railway track beds,with a specific focus on its implementation in China’s rapidly developing railway *** study begins by identifying the limitations of traditional ballasted track beds,especially under the demands of high-speed and heavyload *** then methodically analyzes the advantages of polyurethane-cured track beds,highlighting their improved mechanical properties,including enhanced stability and *** paper further explores the benefits of transitioning to prefabricated polyurethane track beds,emphasizing significant cost reductions,better construction quality,and enhanced *** a detailed review of experimental data and practical applications,the paper demonstrates the efficacy of polyurethane track beds in various railway settings.A critical part of the research involves optimizing the structural parameters of polyurethane track beds to achieve the best balance of mechanical and damping *** conclusion of the paper underscores the potential of polyurethane curing technology as a transformative approach to railway track bed construction,offering a solution to the challenges posed by traditional methods and aligning with the evolving needs of modern railways.

关键词： Polyurethane curing Railway track bed Infrastructure optimization Prefabricated construction

Multi-Dimensional Analysis of China’s“Double Reduction” Policy

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Journal of Contemporary Educational Research 2023年第12期7卷 220-225页

作者： yizhe li Northwest Normal University Lanzhou 730070Gansu ProvinceChina

Under China’s“Double Reduction”policy,although the educational pressure has somewhat reduced,the mechanism of talent selection through examinations still exists,which means competition remains,leading to the internalization of *** article analyzes the challenges faced by the“Double Reduction”policy from historical and current *** reasons for the internalization of education are examined and four recommendations for the further implementation of the“Double Reduction”policy are presented.

关键词： China “Double Reduction”policy Educational reform Internalization

Inhalable metal–organic framework-mediated cuproptosis combined with PD-L1 checkpoint blockade for lung metastasis synergistic immunotherapy

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Acta Pharmaceutica Sinica B 2024年第5期14卷 2281-2297页

作者： Chongzheng Yan Ying liu Guozhi Zhao Huatian Yang Huaiyou Lv Genju li Yuhan li Yaqing Fu Fengqin Sun Yafei Feng yizhe li Zhongxi Zhao Department of Pharmaceutics Key Laboratory of Chemical Biology of Ministry of EducationSchool of Pharmaceutical SciencesCheelloo College of MedicineShandong UniversityJinan 250012China Key University Laboratory of Pharmaceutics&Drug Delivery Systems of Shandong Province School of Pharmaceutical SciencesCheeloo College of MedicineShandong UniversityJinan 250012China

Cuproptosis shows enormous application prospects in lung metastasis ***,the glycolysis,Cu^(+)efflux mechanisms,and insufficient lung drug accumulation severely restrict cuproptosis ***,an inhalable poly(2-(N-oxide-N,N-diethylamino)ethyl methacrylate)(OPDEA)-coated copper-based metal–organic framework encapsulating pyruvate dehydrogenase kinase 1 siRNA(siPDK)is constructed for mediating cuproptosis and subsequently promoting lung metastasis immunotherapy,namely *** inhalation,OMP shows highly efficient lung accumulation and long-term retention,ascribing to the OPDEA-mediated pulmonary mucosa *** tumor cells,OMP is degraded to release Cu2+under acidic condition,which will be reduced to toxic Cu^(+)to induce cuproptosis under glutathione(GSH)***,siPDK released from OMP inhibits intracellular glycolysis and adenosine-5ʹ-triphosphate(ATP)production,then blocking the Cu^(+)efflux protein ATP7B,thereby rendering tumor cells more sensitive to OMP-mediated ***,OMP-mediated cuproptosis triggers immunogenic cell death(ICD)to promote dendritic cells(DCs)maturation and CD8^(+)T cells ***,OMP-induced cuproptosis up-regulates membrane-associated programmed cell death-ligand 1(PD-L1)expression and induces soluble PD-L1 secretion,and thus synergizes with anti-PD-L1 antibodies(aPD-L1)to reprogram immunosuppressive tumor microenvironment,finally yielding improved immunotherapy ***,OMP may serve as an efficient inhalable nanoplatform and afford preferable efficacy against lung metastasis through inducing cuproptosis and combining with aPD-L1.

关键词： Cuproptosis Immunogenic cell death PD-L1 checkpoint blockade Copper-based metal-organic framework Immunotherapy Tumor microenvironment Transmucosal deliveryLung metastasis