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Winter Wheat Yield Estimation Based on Sparrow Search Algorithm Combined with Random Forest:A Case Study in Henan Province,China

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Chinese Geographical Science 2024年第2期34卷 342-356页

作者： SHI xiaoliang chen Jiajun DING Hao YANG Yuanqi ZHANG Yan College of Geomatics Xi’an University of Science and TechnologyXi’an 710054China

Precise and timely prediction of crop yields is crucial for food security and the development of agricultural policies.However,crop yield is influenced by multiple factors within complex growth environments.Previous research has paid relatively little attention to the interference of environmental factors and drought on the growth of winter wheat.Therefore,there is an urgent need for more effective methods to explore the inherent relationship between these factors and crop yield,making precise yield prediction increasingly important.This study was based on four type of indicators including meteorological,crop growth status,environmental,and drought index,from October 2003 to June 2019 in Henan Province as the basic data for predicting winter wheat yield.Using the sparrow search al-gorithm combined with random forest(SSA-RF)under different input indicators,accuracy of winter wheat yield estimation was calcu-lated.The estimation accuracy of SSA-RF was compared with partial least squares regression(PLSR),extreme gradient boosting(XG-Boost),and random forest(RF)models.Finally,the determined optimal yield estimation method was used to predict winter wheat yield in three typical years.Following are the findings:1)the SSA-RF demonstrates superior performance in estimating winter wheat yield compared to other algorithms.The best yield estimation method is achieved by four types indicators’composition with SSA-RF)(R^(2)=0.805,RRMSE=9.9%.2)Crops growth status and environmental indicators play significant roles in wheat yield estimation,accounting for 46%and 22%of the yield importance among all indicators,respectively.3)Selecting indicators from October to April of the follow-ing year yielded the highest accuracy in winter wheat yield estimation,with an R^(2)of 0.826 and an RMSE of 9.0%.Yield estimates can be completed two months before the winter wheat harvest in June.4)The predicted performance will be slightly affected by severe drought.Compared with severe drought year(2011)(R^(2)=0.680)and normal year(2017)(R^(2)=0.790

关键词： winter wheat yield estimation sparrow search algorithm combined with random forest(SSA-RF) machine learning multi-source indicator optimal lead time Henan Province,China

Atom substitution of the solid-state electrolyte Li_(10)GeP_(2)S_(12)for stabilized all-solid-state lithium metal batteries

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Journal of Energy Chemistry 2024年第1期88卷 28-38,I0002页

作者： Zijing Wan Xiaozhen chen Ziqi Zhou xiaoliang Zhong Xiaobing Luo Dongwei Xu State Key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan 430074HubeiChina

Solid-state electrolyte Li_(10)GeP_(2)S_(12)(LGPS)has a high lithium ion conductivity of 12 mS cm^(-1)at room temperature,but its inferior chemical stability against lithium metal anode impedes its practical application.Among all solutions,Ge atom substitution of the solid-state electrolyte LGPS stands out as the most promising solution to this interface problem.A systematic screening framework for Ge atom substitution including ionic conductivity,thermodynamic stability,electronic and mechanical properties is utilized to solve it.For fast screening,an enhanced model Dop Net FC using chemical formulas for the dataset is adopted to predict ionic conductivity.Finally,Li_(10)SrP_(2)S_(12)(LSrPS)is screened out,which has high lithium ion conductivity(12.58 mS cm^(-1)).In addition,an enhanced migration of lithium ion across the LSr PS/Li interface is found.Meanwhile,compared to the LGPS/Li interface,LSrPS/Li interface exhibits a larger Schottky barrier(0.134 eV),smaller electron transfer region(3.103?),and enhanced ability to block additional electrons,all of which contribute to the stabilized interface.The applied theoretical atom substitution screening framework with the aid of machine learning can be extended to rapid determination of modified specific material schemes.

关键词： Atom substitution Solid-state electrolyte Machine learning Stabilized interface

Microstructure Recrystallization and Mechanical Properties of a Cold-Rolled TiNbZrTaHf Refractory High-Entropy Alloy

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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 633-647页

作者： Chuan Rong Jieren Yang xiaoliang Zhao Ke Huang Ying Liu Xiaohong Wang Dongdong Zhu Ruirun chen College of Materials Science and Engineering Sichuan UniversityChengdu610065China Key Laboratory of Air-Driven Equipment Technology of Zhejiang Province Quzhou UniversityQuzhou324000China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin150001China

The equiatomic TiNbZrTaHf alloy was successfully rolled at room temperature with the reduction of ~ 85%. The microstructure and tensile properties were investigated after cold working and annealing. It was determined that the recrystallization temperature of the TiNbZrTaHf alloy between 850 and 900 ℃. Complete recrystallization and normal grain growth occurred, the high stability of single phase was maintained after annealing at 1000, 1200, and 1400 ℃. But the precipitated phase appeared after long term annealing, as seen after 500 h at 1000 ℃. After cold working, the tensile strength and the elongation of TiNbZrTaHf were 1137 MPa and 25.1%, respectively. The annealed alloy has a high tensile strength (σ_(b )= 863 MPa) and ductility (ε_(e )= 28.5%). Moreover, the oxidation of TiNbZrTaHf alloy at elevated temperatures has a significant impact on its mechanical properties. The poor oxidation resistance of TiNbZrTaHf can accelerate tensile failure by inducing fractures at grain boundaries.

关键词： Refractory high entropy alloy Cold rolling Recrystallization Oxidation resistance Mechanical properties

Colloidal quantum dot for infrared-absorbing solar cells:State-oftheart and prospects

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Nano Research Energy 2024年第1期3卷 172-219页

作者： Siyu Zheng Xinyi Mei Jingxuan chen Erik MJJohansson xiaoliang Zhang School of Materials Science and Engineering Beihang UniversityBeijing 100191China Department of Chemistry-Ångström Physical ChemistryUppsala UniversityUppsala 75120Sweden

Colloidal quantum dot(CQD)shows great potential for application in infrared solar cells due to the simple synthesis techniques,tunable infrared absorption spectrum,and high stability and solution-processability.Thanks to significant efforts made on the surface chemistry of CQDs,device structure optimization,and device physics of CQD solar cells(CQDSCs),remarkable breakthroughs are achieved to boost the infrared photovoltaic performance and stability of CQDSCs.In particular,the CQDSC with a high power conversion efficiency of~14%and good stability is reported,which is very promising for infrared-absorbing solar cells.In this review,we highlight the unique optoelectronic properties of CQDs for the development of infrared-absorbing solar cells.Meanwhile,the latest advances in finely controlling surface properties of CQDs are comprehensively summarized and discussed.Moreover,the device operation of CQDSCs is discussed in-depth to highlight the impact of the device structure optimization of CQDSCs on their photovoltaic performance,and the emerging novel types of CQDSCs,such as semitransparent,flexible,and lightweight CQDSCs,are also demonstrated.The device stability of CQDSCs is also highlighted from the viewpoint of practical applications.Finally,the conclusions and possible challenges and opportunities are presented to promote the development steps of the CQDSCs with higher infrared photovoltaic performance and robust stability.

关键词： colloidal quantum dot solar cell photovoltaic performance infrared absorbing solar energy

Regulatory network established by transcription factors transmits drought stress signals in plant

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Stress Biology 2022年第1期2卷 361-382页

作者： Yongfeng Hu xiaoliang chen Xiangling Shen Key Laboratory of Three Gorges Regional Plant Genetics and Germplasm Enhancement Biotechnology Research CenterChina Three Gorges UniversityYichang 443002HubeiChina

Plants are sessile organisms that evolve with a flexible signal transduction system in order to rapidly respond to environmental changes.Drought,a common abiotic stress,affects multiple plant developmental processes especially growth.In response to drought stress,an intricate hierarchical regulatory network is established in plant to survive from the extreme environment.The transcriptional regulation carried out by transcription factors(TFs)is the most important step for the establishment of the network.In this review,we summarized almost all the TFs that have been reported to participate in drought tolerance(DT)in plant.Totally 466 TFs from 86 plant species that mostly belong to 11 families are collected here.This demonstrates that TFs in these 11 families are the main transcriptional regulators of plant DT.The regulatory network is built by direct protein-protein interaction or mutual regulation of TFs.TFs receive upstream signals possibly via post-transcriptional regulation and output signals to downstream targets via direct binding to their promoters to regulate gene expression.

关键词： Plant Drought tolerance Transcription factor Regulatory network Direct target

Preparation of Manganese Oxide and Its Adsorption Properties

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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 1031-1040页

作者：贺跃王海峰 YANG Pan WANG Song chen xiaoliang YANG Chunyuan 王家伟 School of Materials and Metallurgy Guizhou UniversityGuiyang 550025China Guizhou Provincial Engineering Technology Research Center of Manganese Materials for Batteries Tongren Guizhou 554300China Guizhou Provincial Key Laboratory of Metallurgical Engineering and Energy Saving Guiyang 550025China

The in-situ oxidation of manganese sulfate solution with H2O_(2),sodium hypochlorite,potassium permanganate and oxygen as oxidants was investigated by means of SEM,EDS,XRD,BET and infrared analysis,and the effects of different oxidants on the morphology,phase composition,surface properties and specific surface area of manganese oxides were investigated.The experimental results show that the diameter of manganese oxide particles prepared with H_(2)O_(2)is the smallest,about 50 nm,and the specific surface area is the largest,63.8764 m^(2)/g.It has the advantages of abundant surface hydroxyl groups,no introduction of other impurities and large adsorption potential.It is most suitable to be used as an oxidant for oxidizing manganese sulfate solution to prepare manganese oxide by in-situ oxidation.Nano manganese oxide prepard by H_(2)O_(2)in-situ oxidation method is used as adsorbent to adsorb cobalt and nickel impurities in manganese sulfate.When the reaction pH is 6,the reaction time is 30min and the amount of adsorbent is 1.0 g,the adsorption rates of cobalt and nickel impurities in 100ml manganese sulfate solution are 97.59%and 97.67%,respectively.The residual amounts of cobalt and nickel meet the industrial process standard of first-class products(Co,Ni w/%≤0.005)of high-purity manganese sulfate(Hg/t4823-2015)for batteries.The study plays a guiding role in the preparation and regulation of manganese oxide,and provides a new method with high efficiency,purity and adsorbent availability for the preparation of high-purity manganese sulfate solution.

关键词： manganese oxide in situ oxidation adsorbent regulation mechanism physical chemical properties

Modulating the alloying mode in the doping-induced synthesis of Au-Pd nanowires

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Nano Research 2024年第4期17卷 3334-3343页

作者： Hui Jin xiaoliang Wei Lecheng Zhao Jialong Yu Qiao Pan Shumin Li Qian Wang Zhaotong Yuan Dan Yang Donghui Zhao Hongyu chen Yawen Wang Institute of Advanced Synthesis School of Chemistry and Molecular EngineeringJiangsu National Synergistic Innovation Center for Advanced MaterialsNanjing Tech UniversityNanjing 211816China School of Science Westlake UniversityHangzhou 310064China Institute of Natural Sciences Westlake Institute for Advanced StudyHangzhou 310064China

Heterogeneous doping is one effective strategy for synthesizing metal alloy nanowires.Herein,the heterogeneous doping processes of Pd on the ultrathin Au nanowires were systematically modulated and investigated.Au-Pd alloy nanowires with various morphologies and lattice structures can be obtained by adjusting the morphology of the precursor Au nanowires and the kinetics of the heterogeneous doping processes.The effects of the rate of Pd reduction and the concentration of the ligand oleylamine(OAm)on the Pd deposition and alloying mode were articulated.Generally,as the Pd deposition rate decreases,the Pd deposition and alloying mode switches from the island-forming Stransky–Krastanov(SK)mode to the epitaxial Frank-van der Merwe(FM)mode,and eventually to an unconventional twisting alloying mode,where the interdiffusion of Pd and Au causes drastic rearrangement of the lattice structure and formation of helical structures.The kinetics-related variation of alloying mode could also be observed in the Au-Ag nanowires,demonstrating a general design principle for the synthesis of alloy nanostructures.In addition,the electrocatalytic performance of various Au-Pd nanowires was evaluated,and the alloy nanowire formed via the SK mode was found to be an excellent electrocatalyst for oxygen reduction and ethanol oxidation.

关键词： gold nanowires Au-Pd alloy oleylamine post-synthetic modification

A flexible dual-function capacitive sensor enhanced by looppatterned fibrous electrode and doped dielectric pillars for spatial perception

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Nano Research 2023年第5期16卷 7550-7558页

作者： Yongsong Luo xiaoliang chen Xiangming Li Hongmiao Tian Liang Wang Jinyou Shao Micro-and Nano-technology Research Center State Key Laboratory for Manufacturing Systems EngineeringXi’an Jiaotong UniversityXi’an 710049China Frontier Institute of Science and Technology(FIST) Xi’an Jiaotong UniversityXi’an 710049China

The integrated perception capable of detecting and monitoring varieties of activities is one of the ultimate purposes of wearable electronics and intelligent robots.Limited by the space occupation,it lacks practical feasibility to stack multiple types of single sensors on each other.Herein,a high-sensitivity dual-function capacitive sensor with proximity sensing and pressure sensing is proposed.The fringing electric field can be confined in the proximity-sensitive area by fibrous loop-patterned electrode,leading to more stolen charges when object approaching and thus a high proximity sensitivity.The high-permittivity doped structured dielectric layer reduces the compressive stiffness and enhances the rate of compression-caused increase in the equivalent relative permittivity of the dielectric layer,resulting in a larger increase in capacitance and thus a high pressure sensitivity.The electrodes and dielectric layer together compose the capacitor and act as the sensor without taking up additional space.The decoupling of proximity-sensing and pressure-sensing modes can be achieved by decrease or increase in capacitance.Combined with array distribution and sequential scanning,the sensors can be used for detection of motion trajectory,contour recognition,pressure distribution.

关键词： capacitive proximity sensing pressure sensing fibrous microstructuring doping

Winding Function Theory Based Thrust Calculation on Nested-loop Secondary Linear Machine Adapted to Linear Metro

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CES Transactions on Electrical Machines and Systems 2023年第2期7卷 153-162页

作者： Yaping Zhang Jian Ge Wei Xu Hao Tang Yang Gao xiaoliang chen Shihu Su Zhen Bao the State Key Laboratory of Advanced Electromagnetic Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China IEEE Xiangyang CRRC Motor Technology Co. Ltd.Xiangyang 441000China CRRC Zhuzhou Institute Co. Ltd.Zhuzhou 412001China Guangzhou Metro Group Co. Ltd.Guangzhou 510330China the Zhuzhou CRRC Times Electric Co. Ltd.and CRRC Zhuzhou Motor Co.Ltd.Zhuzhou 412001China

With advantages of strong drive capability,nested-loop secondary linear machine(NLS-LM)has great potentiality in linear metro.For its secondary structure with multiple loops,it is difficult to calculate the electromagnetic thrust of NLS-LM reasonably.Hence,in this paper,one thrust calculation method is proposed considering variable loop inductance and transient loop current.Firstly,to establish the secondary winding function,the modeling domain is confined to a limited range,and the equivalent loop span is employed by analyzing the coupling relationship between primary and secondary.Then,in order to obtain the secondary flux density,the transient secondary current is solved based on the loop impedance and induced voltage.Finally,the electromagnetic thrust can be calculated reasonably by the given primary current sheet and the calculated secondary flux density.Comprehensive simulations and experiments have demonstrated the effectiveness of the proposed method.

关键词： Nested-loop secondary Linear metro Electro-magnetic thrust Finite element algorithm(FEA) Transient nested-loop current Winding function