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Operation power consumption and verification tests of a trenching device for orchards in Xinjiang based on discrete element

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International Journal of Agricultural and Biological Engineering 2021年第1期14卷 133-141页

作者： Chen ma Jiangtao Qi za Kan Shaojie Chen Hewei Meng College of Mechanical and Electrical Engineering Shihezi UniversityShihezi 832000XinjiangChina College of Mechanical and Electronic Engineering Xinjiang Vocational UniversityUrumqi 830013China Key Laboratory of Northwest Agricultural machinery of the Ministry of Agriculture Shihezi 832000XinjiangChina Ruiyida machinery Equipment Co. Ltd.Shihezi Development ZoneShihezi 832000XinjiangChina

According to the agronomic requirements of orchard planting pattern and fertilization in Xinjiang,the soil particle models and a soil-trenching device interaction model were established by using discrete element simulation software in order to find out the law of influence of structure parameters and working parameters on the operation power consumption of a segmented cutting trenching device;moreover,its cutting process was simulated according to the response surface test *** to the results of research on the influence of forward speed,cutter disk speed and cutter disk combination on the operation power consumption of the segmented cutting trenching device,the law of their influence on the operation power consumption in descending order is forward speed,cutter disk combination,cutter disk *** to the response surface test result,the following influential factor parameter combination has been obtained:forward speed 815 m/h,cutter disk speed 112 r/min,cutter disk combination A(cut angle 150°,bent angle 60°and working width 133 mm),cutter disk combination B(cut angle 180°,bent angle 90°and working width 166 mm),and trenching operation power consumption-optimization results were verified through field *** to the verification,the results showed a high accuracy of the simulation,with a relative error mean of 3.18%between the theoretical value and the field test *** study can provide a reference for the energy-saving design of orchard trenching devices.

关键词： trenching device discrete element orchard power consumption simulation analysis parameter optimization

Design and parameter optimization of spiral-dragon type straw chopping test rig

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International Journal of Agricultural and Biological Engineering 2020年第1期13卷 47-56页

作者： Pengbo ma Liqiao Li Baoqin Wen Yunheng Xue za Kan Jingbin Li College of Mechanical Electrical Engineering Shihezi UniversityShihezi 832000China Key Laboratory of Northwest Agricultural equipment Ministry of Agriculture and Rural AffairsShihezi 832000China

In order to address the problems of large chop length,high energy consumption and poor chopping effect that were associated with a horizontal total mixed rations(TMR)mixer,a straw chopping device was designed;further,its structure and working principle were *** this study,wheat straw was chosen as the test *** number of processing times,number of fixed blades,cutting speed,number of tooth plates and the inclined angle of the box were considered as the test *** standard straw length rate and average power were used as evaluation indices for conducting the orthogonal rotation combination experiment with five factors and five levels of quadratic *** experimental results denoted that the order of influencing factors on the standard straw length rate can be given as follows:the number of processing times,number of fixed blades,cutting speed,number of tooth plates and inclined angle of the *** order of the influence of each factor on the average power can be given as follows:the cutting speed,number of fixed blades and number of tooth ***,the optimum structural and working parameters of the device can be determined as follows:linear cutting speed of 17-20 m/min,box inclined angle of 70°-80°,20-23 fixed blades,5-6 processing times and 4-7 tooth *** such a circumstance,the standard straw length rate reached up to 70.5%-77.4%and the average power was low at 5.8-7 *** results can be used as reference for designing a chopping device for a TMR mixer.

关键词： total mixed rations straw chopping device parameter optimization

A　NEW　INGENOL　ESTER　FROM　EUPHORBIA　PETIOLATA

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Chinese Chemical Letters 1996年第5期7卷 439-440页

作者： Shi, YP ma, B Jia, ZJ Lahham, J saleh, sa LANZHOU UNIV INST ORGAN CHEMSTATE KEY LAB APPL ORGAN CHEMLANZHOU 730000PEOPLES R CHINA

Abstract: A new monoester of the tetracyclic diterpene ingenol was isolated from Euphorbia petiolata and its structure was elucidated by spectroscopic methods and chemical transformationas ingenol-3-O-(2'E, 4'Z)-tetra...

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Effect of rare-earth doping on adsorption of carbon atom on ferrum surface and in ferrum subsurface:A first-principles study

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Journal of Rare Earths 2021年第9期39卷 1144-1150页

作者： Yang Yang Xiang Zhou Faqing Pan Zuju ma Rongjian sa Jun Zheng Qimin Wang Key Laboratory of Green Fabrication and Surface Technology of Advanced Metal materials(Ministry of Education) Research Center of Modem Surface and Interface EngineeringAnhui University of TechnologyMaanshan 243002China School of materials Science and Engineering Anhui University of TechnologyMaanshan 243002China Institute of Oceanography Ocean CollegeMinjiang UniversityFuzhou 350108China School of Electromechanical Engineering Guangdong University of TechnologyGuangzhou 510006China

The adsorption of carbon atom on Fe surface and in Fe subsurface with and without rare earth(La and Ce)substitution in the surface layer and subsurface layer was studied by first-principles *** carbon atom is predicted to adsorb at hollow and long bridge site on Fe(100)and Fe(110),***,the carbon atom shifts to occupy preferentially hollow site on both Fe(100)and Fe(110)with rare earth atom doping at surface *** lower adsorption energies involved with stronger adsorption abilities were obtained for carbon atoms on Fe surface with rare earth doping at surface layer,which was determined by the electronic structure of the surface *** La atom was pulled out the surface after carbon adsorption due to strong interaction of La-C,which is consistent with the more charge *** the subsurface region,the carbon atom prefers to occupy at octahedral site with rare earth doping at surface layer in Fe *** strong adsorption energies of the carbon atoms on Fe surface and in Fe subsurface with rare earth pose relevant insights into the interaction between carbon and rare earth,which helps to understanding the influence mechanism of rare earth in carburizing.

关键词： Carburizing Rare earth First-principles Adsorption energy Electronic structure

Enhancing hydrogen evolution of MoS_(2) basal planes by combining single-boron catalyst and compressive strain

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Frontiers of physics 2020年第6期15卷 1-12页

作者： Zhitao Cui Wei Du Chengwei Xiao Qiaohong Li Rongjian sa Chenghua Sun Zuju ma School of Environmental and materials Engineering Yantai UniversityYantai 264005China School of materials Science and Engineering Anhui University of TechnologyMaanshan 243002China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Institute of Oceanography Ocean CollegeMinjiang UniversityFuzhou 350108China Department of Chemistry and Biotechnology Faculty of ScienceEngineering&TechnologySwinburne University of TechnologyHawthornVIC 3122Australia

M0 S2 is a promising candidate for hydrogen evolution reaction(HER),while its active sites are mainly distributed on the edge sites rather than the basal plane ***,a strategy to overcome the inertness of the M0 S2 basal surface and achieve high HER activity by combining single-boron catalyst and compressive strain was reported through density functional theory(DFT)*** ab initio molecular dynamics(AIMD)simulation on B@MoS2 suggests high thermodynamic and kinetic *** found that the rather strong adsorption of hydrogen by B@MoS2 can be alleviated by stress *** optimal stress of -7%can achieve a nearly zero value of △Gh(〜-0.084 eV),which is close to that of the ideal Pt-saCs for *** novel HER activity is attributed to(i)the Bdoping brings the active site to the basal plane of M0 S2 and reduces the band-gap,thereby increasing the conductivity;(ii)the compressive stress regulates the number of charge transfer between(H)-(B)-(MoS2),weakening the adsorption energy of hydrogen on B@***,we constructed a SiN/B@MoS2 heterojunction,which introduces an 8.6%compressive stress for B@MoS2 and yields an ideal AGh-This work provides an effective means to achieve high intrinsic HER activity for M0 S2.

关键词： M0S2 stress engineering single-atom catalyst HER charge transfer DFT heteroj unctions

An interpretable machine learning strategy for pursuing high piezoelectric coefficients in (K_(0.5)Na_(0.5))NbO_(3)-based ceramics

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npj Computational materials 2023年第1期9卷 1-11页

作者： Bowen ma Xiao Wu Chunlin Zhao Cong Lin Min Gao Baisheng sa Zhimei Sun College of materials Science and Engineering Fuzhou UniversityFuzhou 350108China School of materials Science and Engineering Beihang UniversityBeijing 100191China

Perovskite-type lead-free piezoelectric ceramics allow access to illustrious piezoelectric coefficients(d33)through intricate composition design and experimental *** a swift and accurate technology for identifying(K,Na)NbO_(3)(KNN)-based ceramic compositions with high d33 in exceedingly large“compositional”space will establish an innovative research paradigm surpassing the traditional empirical trial-and-error ***,we demonstrate an interpretable machine learning(ML)framework for quick evaluation of KNN-based ceramics with high d33 based on data from published ***,a thorough feature construction was carried out from the global and local dimensions to establish tree regression models with d33 as the target ***,the feature-property mapping rules of KNN-based piezoelectric ceramics are further optimized through feature *** intuitively understand the correlation mechanisms between ML regression targets and features,the sure independence screening and sparsifying operator(SISSO)method was employed to extract the essential descriptors to explain d33.A straightforward descriptor,e^((NMB-MVB))·ST=(IDA)^(2),consisting of only four easily accessible parameters,can accelerate the evaluation of a series of novel KNN-based ceramics with high d33 while exhibiting strong theoretical *** work not only provides a tool for the rapid discovery of high piezoelectric performance in KNN-based ceramics but also offers a data-driven route for the design of property descriptors in perovskites.

关键词： ceramics ceramic piezoelectric

TM_(3)(TM=V,Fe,Mo,W)single-cluster catalyst confined on porous BN for electrocatalytic nitrogen reduction

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Journal of materials Science & Technology 2022年第13期108卷 46-53页

作者： Shuaishuai Gao Zuju ma Chengwei Xiao Zhitao Cui Wei Du Xueqin Sun Qiaohong Li Rongjian sa Chenghua Sun School of Environmental and materials Engineering Yantai UniversityYantai 264005China School of materials Science and Engineering Anhui University of TechnologyMaanshan 243002China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Institute of Oceanography Ocean CollegeMinjiang UniversityFuzhou 350108China College of Chemical Engineering and Energy Technology Dongguan University of TechnologyDongguan 523808China Department of Chemistry and Biotechnology Faculty of ScienceEngineering&TechnologySwinburne University of TechnologyHawthornVIC 3122Australia

Confined metal clusters as sub-nanometer reactors for electrocatalytic N_(2) reduction reaction(eNRR)have received increasing attention due to the unique metal-metal interaction and higher activity than singleatom ***,the inspiration of the superior capacitance and unique microenvironment with regular surface cavities of the porous boron nitride(p-BN)nanosheets,we systematically studied the catalytic activity for NRR of transition-metal single-clusters in the triplet form(V_(3),Fe_(3),Mo_(3) and W_(3))confined in the surface cavities of the p-BN sheets by spin-polarized density functional theory(DFT)*** a two-step screening strategy,Mo_(3)@p-BN was found to have high catalytic activity and selectivity with a rather low limiting potential(-0.34 V)for the *** anchored Mo_(3) singlecluster can be stably embedded on the surface cavities of the substrate preventing the diffusion of the active Mo *** importantly,the Mo atoms in the Mo_(3) single-cluster would act as“cache”to accelerate electron transfer between active metal centers and nitrogen-containing intermediates via the intimate Mo-Mo *** cooperation of Mo atoms can also provide a large number of occupied and unoccupied d orbitals to make the"donation-backdonation"mechanism more *** work not only provides a quite promising electrocatalyst for NRR,but also brings new insights into the rational design of triple-atom NRR catalysts.

关键词： Electrocatalytic N_(2)reduction Density functional theory Single-cluster Porous boron nitride

Chemoenzymatic synthesis amphiphilic H-shaped copolymer and its self-assembly behavior

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Science China Chemistry 2009年第12期52卷 2336-2341页

作者： ShuWei Wang Bao Zhang Peng Ai Ming Zhu Wei Wang ZhongPeng sa LiNa ma YaPeng Li Alan G. macDiarmid Institute of Jilin University Changchun 130012 China Department of Bioengineering College of Pharmacy Jilin University Changchun 130021 China

ABA triblock copolymers were synthesized by dihydroxyl-capped PEO initiated enzymatic ring-opening polymerization (eROP) of ε-CL in the presence of biocatalyst Novozyme 435. The chains ended with hydroxyl of block copolymers were modified by the esterification of 2,2-dichloro acetyl chloride (DCAC) to obtain the tetrafunctional macroinitiator, which was used in the ATRP of 4-vinylpyridine (4-VP). CuCl/HMTETA was used as the catalyst system in the ATRP of 4-VP to acquire the H-shaped block copolymers (PVP)2-b-PCL-b-PEG-b-PCL-b-(PVP)2. The H-shaped block copolymers were characterized by FTIR, NMR, and GPC. Copolymers with high molecular weights (M n = 46121 g/mol) and low polydispersities (M w/M n = 1.30) were prepared. Moreover, the morphology of the copolymer was examined with dynamic light scattering (DLS) and atomic force microscopy (AFM). Spherical micelles with a diameter of 70 nm in aqueous solution were obtained.

关键词： atom transfer radical polymerization (ATRP) enzymatic ring-opening polymerization (eROP) amphiphilic block copolymer

Understanding and modifications on lithium deposition in lithium metal batteries

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Rare Metals 2022年第8期41卷 2800-2818页

作者： Qin-Ya Yang Zhao Yu Yao Li Wang Zhang hao-Wen Yuan Hong-Jie Li Wei ma Shen-Min Zhu sa Li State Key Laboratory of Metal matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai200240China School of materials Science and Engineering Tongji UniversityShanghai201804China

Lithium metal has been considered as an ultimate anode choice for next-generation secondary batteries due to its low density,superhigh theoretical specific capacity and the lowest voltage ***,uncontrollable dendrite growth and consequently large volume change during stripping/plating cycles can cause unsatisfied operation efficiency and serious safety concern,restraining its commercial use for the last 40 *** widely used lithium-ion battery is approaching its theoretical limit at present,it is increasingly urgent to develop new energy storage equipment with sufficient practical ***,two important processes of lithium deposition,nucleation and growth on lithium metal anode are *** three-dimensional(3 D)porous anodes with unique structure and dynamic surface conditions,as one of the most efficient designs on dendrites suppression,are specifically discussed in terms of their beneficial adjustment on the dendrite *** on current designs and prospects on future advanced porous anode are explored in the end.

关键词： Lithium metal batteries Lithium nucleation Dendrites growth Porous anodes