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Research on the Working Mechanism and Virtual Design for Cleaning Element in Brush Shape of the Sugarcane Harvester

厦门大学学报（自然科学版） 2002年第S1期41卷 137-138页

作者： li shang-ping, meng yan-mei, ma fang-lan, tan hong-hao, chen wei-xu (College of Mechanical Engineering, Guangxi University, Nanning 530004 , China)

The cleaning element is the key part to the small w ho le-stall sugarcane harvester, which is suitable to the highland. And it is the bottleneck of the design of the small sugarcane harvester. The working mechanism of centrifugal cleaning method of the cleaning element in brush shape is based on the high speed rotating cleaning element that push, scrub, and strike the sta lk to separate the leaves from the sugarcane. The paper elaborated the worki ng mechanism of cleaning element in brush shape of the sugarcane harvester, and analyzed the state of cleaning procedure and the reacting force that the cleanin g element was subjected. Combined with the earlier stage experiments and researc hes, it was found out that the factors, which affect the cleaning efficiency and fatigue life of cleaning element, were quite many, and the factors were complex and random. So it was difficult to analyze and design cleaning element in theor y. Moreover, if the design parameters were got from experiment it would be time consuming, laborious, and costly. The method of numerical value simulation ortho gonal experiment is used to analyze the reacting force by means of establishing finite element analysis model for cleaning element on ANSYS. According to orthog onal experiment principle, the different parameter groups were made to do finite element calculation. And then orthogonal experiment analysis and regression ana lysis were made to find out the effect on the calculated result that was caused by the changes of different parameter groups, and get optimal design parameters of cleaning element. In conclusion, this virtual design method is a quick and ef ficient way in innovative mechanical product design. This method economizes mate rial, labor, and time, and then it is the right way of high efficiency and speed to reduce the development period, and increase the quality of product and the r atio of successful development at once.

关键词： cleaning element finite element analysis orthog onal experiment regression analysis

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Branch-Chain-Rich Diisopropyl Ether with Steric Hindrance Facilitates Stable Cycling of lithium Batteries at-20℃

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Nano-Micro Letters 2024年第10期16卷 121-135页

作者： Houzhen li Yongchao Kang Wangran wei Chuncheng yan Xinrui ma hao chen Yuanhua Sang hong liu Shuhua Wang State Key Laboratory of Crystal materials Shandong UniversityJinan 250100People's Republic of China

li metal batteries(LMBs)offer signifi-cant potential as high energy density alternatives;nev-ertheless,their performance is hindered by the slow desolvation process of electrolytes,particularly at low temperatures(LT),leading to low coulombic efficiency and limited cycle ***,it is essential to opti-mize the solvation structure thereby achieving a rapid desolvation process in LMBs at ***,we introduce branch chain-rich diisopropyl ether(DIPE)into a 2.5 M li bis(fluorosulfonyl)imide dipropyl ether(DPE)elec-trolyte as a co-solvent for high-performance LMBs at-20℃.The incorporation of DIPE not only enhances the disorder within the electrolyte,but also induces a steric hindrance effect form DIPE’s branch chain,excluding other solvent molecules from li+solvation *** of these factors contribute to the weak interactions between li^(+)and solvent molecules,effectively reducing the desolvation energy of the ***,li(50μm)||LFP(mass loading~10 mg cm^(-2))cells in DPE/DIPE based electrolyte demonstrate stable performance over 650 cycles at-20℃,delivering 87.2 mah g^(-1),and over 255 cycles at 25℃ with 124.8 mah g^(-1).DIPE broadens the electrolyte design from molecular structure considera-tions,offering a promising avenue for highly stable LMBs at LT.

关键词： Solvation structure li metal battery Low temperature Steric hindrance Disorder

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A hybrid machine learning optimization algorithm for multivariable pore pressure prediction

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Petroleum Science 2024年第1期21卷 535-550页

作者： Song Deng hao-Yu Pan Hai-Ge Wang Shou-Kun xu Xiao-Peng yan Chao-wei li Ming-Guo Peng hao-ping Peng lin Shi meng Cui Fei Zhao School of Petroleum and Natural Gas Engineering Changzhou UniversityChangzhou213164JiangsuChina Tubular Goods Research Institute of CNPC Beijing102249China CNPC Engineering Technology R&D Company limited Beijing102206China

Pore pressure is essential data in drilling design,and its accurate prediction is necessary to ensure drilling safety and improve drilling *** methods for predicting pore pressure are limited when forming particular structures and *** this paper,a machine learning algorithm and effective stress theorem are used to establish the transformation model between rock physical parameters and pore *** study collects data from three *** 1 had 881 data sets for model training,and Wells 2 and 3 had 538 and 464 data sets for model *** this paper,support vector machine(SVM),random forest(RF),extreme gradient boosting(XGB),and multilayer perceptron(MLP)are selected as the machine learning algorithms for pore pressure *** addition,this paper uses the grey wolf optimization(GWO)algorithm,particle swarm optimization(PSO)algorithm,sparrow search algorithm(SSA),and bat algorithm(BA)to establish a hybrid machine learning optimization algorithm,and proposes an improved grey wolf optimization(IGWO)*** IGWO-MLP model obtained the minimum root mean square error(RMSE)by using the 5-fold cross-validation method for the training *** the pore pressure data in Well 2 and Well 3,the coefficients of determination(R^(2))of SVM,RF,XGB,and MLP are 0.9930 and 0.9446,0.9943 and 0.9472,0.9945 and 0.9488,0.9949 and *** achieves optimal performance on both training and test data,and the MLP model shows a high degree of *** indicates that the IGWO-MLP is an excellent predictor of pore pressure and can be used to predict pore pressure.

关键词： Pore pressure Grey wolf optimization Multilayer perceptron Effective stress machine learning

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Optimal search path planning of UUV in battlefeld ambush scene

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Defence Technology（防务技术） 2024年第2期32卷 541-552页

作者： wei Feng yan ma Heng li Haixiao liu Xiangyao meng Mo Zhou Naval Research Institute Beijing100161China

Aiming at the practical application of Unmanned Underwater Vehicle(UUV)in underwater combat,this paper proposes a battlefield ambush scene with UUV considering ocean ***,by establishing these mathematical models of ocean current environment,target movement,and sonar detection,the probability calculation methods of single UUV searching target and multiple UUV cooperatively searching target are given ***,based on the Hybrid Quantum-behaved Particle Swarm Optimization(HQPSO)algorithm,the path with the highest target search probability is ***,through simulation calculations,the influence of different UUV parameters and target parameters on the target search probability is analyzed,and the minimum number of UUVs that need to be deployed to complete the ambush task is demonstrated,and the optimal search path scheme is *** method proposed in this paper provides a theoretical basis for the practical application of UUV in the future combat.

关键词： Battlefield ambush Optimal search path planning UUV path Planning Probability of cooperative search

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Megafossils of Betulaceae from the Oligocene of Qaidam Basin and their paleoenvironmental and phytogeographic implications

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Plant Diversity 2024年第1期46卷 101-115页

作者： Tao yang Jia-hao Cai yan-Zhi Dai hong-Yu chen Lei Han li Zhang wei-Yu liang xu-Jun li Wen-Jia li Jing-Yu Wu San-ping Xie De-Fei yan School of Earth Sciences and Key Laboratory of Mineral Resources in Western China(Gansu Province) Lanzhou UniversityLanzhou 730000China Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PaleoenvironmentChinese Academy of SciencesNanjing 210008China Center for Research and Education on Biological Evolution and Environments School of Earth Sciences and EngineeringNanjing UniversityNanjing 210023China

Understanding the paleoenvironment and phytogeographical history of the Tibetan Plateau,China relies on discovering new plant *** Qaidam Basin has long been regarded as an ideal‘field laboratory’to investigate the paleoclimate and paleobiological evolution of the northern Tibetan ***,fossil angiosperms from the Qaidam Basin are rare,and our knowledge of its paleovegetation is ***,we report fossil leaves and fruits of Betulaceae found from the Oligocene shangganchaigou Formation of northwestern Qaidam Basin(Huatugou area).Comparative morphological analysis led us to assign the fruits to the Betula subgenus Betula and the leaves to Carpinus *** findings,together with other reported fossil plants from the same locality,reveal a close floristic linkage between the Qaidam Basin and Europe during the *** northern pathway of this floristic exchange may have crossed through the Qaidam Basin during the late *** floristic linkage may have been facilitated by the continuous narrowing of the Turgai Strait and stronger westerlies,which transported moisture and provided favorable climatic ***,fossil plants collected from the Qaidam Basin suggest that during the Oligocene this region had warm and humid deciduous broad-leaf forest,which differs from the region’s modern vegetation and indicates that the Qaidam Basin may have been a suitable region for these plants to flourish and spread during the Oligocene.

关键词： Paleoenvironment Biogeography Betulaceous fossil Qaidam basin Tibetan Plateau Oligocene

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Work-function-induced interfacial electron redistribution of MoO_(2)/WO_(2) heterostructures for high-efficiency electrocatalytic hydrogen evolution reaction

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Rare Metals 2024年第2期43卷 489-499页

作者： Tong-Fei li Jing li Lu-ping Zhang Jia-wei Ke meng-Xing Fan li-fang Zhang cheng-wei Deng Yi Sun Tao Qian cheng-lin yan School of Chemistry and Chemical Engineering Nantong UniversityNantong226019China Jiangsu Key Laboratory of New Power Batteries Jiangsu Collaborative Innovation Centre of Biomedical Functional MaterialsSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing210023China Aerospace Hydrogen Energy Technology(shanghai)Co.Ltd. Shanghai201800China Key Laboratory of Core Technology of High Specific Energy Battery and Key materials for Petroleum and Chemical Industry College of EnergySoochow UniversitySuzhou215006China light Industry Institute of Electrochemical Power Sources Suzhou215006China

The engineering of the electronic configurations of active sites,together with the production of more accessible active sites through heterostructure design,has been established as a forceful methodology for boosting water electrolysis ***,a facile approach is developed to fabricate well-dispersed MoO_(2) and WO_(2) nanoparticles with abundant heterointerfaces entrapped in N,P-doped carbon nanofibers(referred to as MoO_(2)/WO_(2)@N,P-CNFs hereafter)as hydrogen evolution reaction(HER)electrocatalysts in alkaline and acidic *** spectroscopic analyses and theoretical findings manifest that the heterointerface formed by the work function modulation of MoO_(2)/WO_(2) triggers the spontaneous electron redistribution from MoO_(2)to WO_(2) and a built-in electric field,which is essential to promote water adsorption,optimize the H-intermediate adsorption energy,result in the enhanced charge transfer efficiency,and ultimately increase the intrinsic HER ***,the intimate confinement of MoO_(2)/WO_(2) heterostructures in the porous carbon substrate can restrain the active sites from unfavorable coarsening and detachment,thus ensuring facilitated HER kinetics and outstanding structural *** a result,MoO_(2)/WO_(2)@N,P-CNFs exhibit superior catalytic HER performance in acidic and basic solutions,requiring 118 and 95 mV overpotentials to achieve 10 ma·cm^(−2),respectively,surpassing a number of reported non-noble metal-based *** work provides guidelines for the rational design and construction of special metallic heterocomponents with optimized interfacial electronic structure for various electrochemical technologies.

关键词： Electrospinning MoO_(2)/WO_(2) heterostructure Work function Hydrogen evolution reaction

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Efficacy and Safety of Chinese Herbal Medicines Combined with Chemical Drugs for Alzheimer's Disease:A Systematic Review and Meta-Analysis

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World Journal of Traditional Chinese Medicine 2024年第1期10卷 1-13页

作者： li xu Wen-Jun chen Cai-Jun Tian yan Zhang yan ma Tian-hao li hong-Jie liu Zhe Zhang Department of the First College English College of Foreign LanguageShandong University of Traditional Chinese MedicineJinanChina Department of Oncology Linyi People's HospitalLinyiChina Department of Internal Medicine of Traditional Chinese Medicine The First Clinical CollegeShandong University of Traditional Chinese MedicineJinanChina Department of Chinese materia Medica College of Traditional Chinese MedicineShandong University of Traditional Chinese MedicineJinanChina Department of Medicinal Chemistry College of PharmacyShandong University of Traditional Chinese MedicineJinanChina Community Healthcare Center Shenzhen Traditional Chinese Medicine HospitalShenzhenChina Department of Fundamentals of Traditional Chinese Medicine School of Traditional Chinese MedicineJinan UniversityGuangzhouChina Shandong Co-Innovation Center of Classic TCM Formula College of Traditional Chinese MedicineShandong University of Traditional Chinese MedicineJinanChina

Objective:To evaluate the efficacy and safety of Chinese herbal medicines(CHMs)combined with chemical drugs for the treatment of Alzheimer's disease(AD).materials and Methods:Databases were searched to retrieve randomized controlled trials(RCTs)of CHMs combined with tacrine,galantamine,rivastigmine,donepezil,or memantine,following strict inclusion and exclusion *** research papers published in English,Chinese,and Japanese were *** primary outcome was the mini-mental state examination(MMSE)score and the secondary outcomes were AD assessment scale cognitive subscale(ADAS-Cog)score and safety ***-analysis was carried out using Rev man 5.3 and subgroup analysis was conducted to identify the sources of ***:A total of 15 RCTs with 1386 participants were included in this *** donepezil was used in the retrieved ***-analyses showed that the combination of CHMs with donepezil led to significant improvement in the MMSE score(Z=9.45;Pweighted mean difference[WMD]=2.68,95%confidence interval[CI]:2.12-3.24)and a significant decrease in the ADAS-Cog score(Z=5.53;Plieved adverse events such as insomnia(risk ratio[RR]=0.20,95%CI:0.06-0.68;P=0.01)and hive(RR=0.10;95%CI:0.01-0.73;P=0.02).Conclusions:The combination of CHMs with a chemical drug like donepezil led to significant improvements in patient cognition as well as a better safety profile when compared to the application of a chemical drug alone.

关键词： Alzheimer's disease Chinese herbal medicine donepezil memantine meta-analysis randomized controlled trials rivastigmine

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lipid nanovehicles overcome barriers to systemic RNA delivery: lipid components, fabrication methods, and rational design

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Acta Pharmaceutica Sinica B 2024年第2期14卷 579-601页

作者： Jing yan hao Zhang Guangfeng li Jiacan Su yan wei Can xu Institute of Translational Medicine Shanghai UniversityShanghai 200444China Institute of Medicine Shanghai UniversityShanghai 200444China Department of Orthopedics Xinhua HospitalShanghai Jiao Tong University School of MedicineShanghai 200092China Department of Orthopedics Shanghai Zhongye HospitalShanghai 200941China Organoid Research Center Shanghai UniversityShanghai 200444China Department of Gastroenterology Changhai HospitalShanghai 200433China

lipid nanovehicles are currently the most advanced vehicles used for RNA delivery,as demonstrated by the approval of patisiran for amyloidosis therapy in *** illuminate the unique superiority of lipid nanovehicles in RNA delivery,in this review,we first introduce various RNA therapeutics,describe systemic delivery barriers,and explain the lipid components and methods used for lipid nanovehicle ***,we emphasize crucial advances in lipid nanovehicle design for overcoming barriers to systemic RNA ***,the current status and challenges of lipid nanovehicle-based RNA therapeutics in clinical applications are also *** objective is to provide a comprehensive overview showing how to utilize lipid nanovehicles to overcome multiple barriers to systemic RNA delivery,inspiring the development of more high-performance RNA lipid nanovesicles in the future.

关键词： lipid nanovehicles RNAtherapeutics Barriers to systemicRNA delivery lipid components Fabricationmethods lipid nanovehicledesign Extrahepatictissue targeting Organ tropism

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Enhanced hydrogen evolution performance by 3D ordered macroporous Ru-CoP@NC electrocatalysts

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Rare Metals 2024年第3期43卷 1095-1107页

作者： chen-chen Zhang Sheng wei li-Xian Sun Yi-fang Ouyang Fen xu Hai-liang Chu hong-GePan li-Xin chen xue-Zhang Xiao School of material Science and Engineering Guilin University of Electronic TechnologyGuilin541004China School of Chemistry and Chemical Engineering Guangxi UniversityNanning530004China Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen518055GuangdongChina Institute of Science and Technology for New Energy Xi'an Technological UniversityXi'an710021China School of materials Science and Engineering Zhejiang UniversityHangzhou310058China

Electrocatalytic water splitting coupled with sustainable energies is identified as an environmentally friendly and renewable strategy to generate high-quality hydrogen for the fuel ***,the main challenge is to develop high performance,low cost and chemically stable electrocatalysts to decline the energy barriers and enhance the sluggish kinetics of hydrogen evolution reaction(HER).Herein,a three-dimensional hierarchically ordered macroporous Ru-CoP@NC electrocatalyst(3DOM Ru-CoP@NC)derived from ordered macro-microporous metal-organic frameworks has been prepared using the precursor@template and double-solvent *** prepared 3DOM Ru-CoP@NC catalyst exhibits an overpotential of 15 mV(j=10 ma·cm^(-2))and a reaction Tafel slope of 38 mV·dec^(-1)in alkaline electrolyte,which are superior to commercial Pt@C ***,the overpotential and reaction Tafel slope of this catalyst in acidic media are 45 mV and 50 mV·dec^(-1),*** outstanding HER activities of 3DOM Ru-CoP@NC catalysts are ascribed to the 3D highly interconnectedreticular nanospaces that can increase effective reaction active *** N dope d carbon framework improves the electronic properties and ***,the strong interaction of Ru and CoP nanoparticles also boosts the HER *** results indicate that 3DOM Ru-CoP@NC catalysts with high catalytic activities have a broad application prospect in the future.

关键词： Hydrogen evolution reaction Template method 3D ordered macroporous Ru-CoP@NC

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Characteristics and genesis of shoal facies reservoir of the Lower Ordovician Tongzi Formation in southeastern Sichuan Basin,China

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Petroleum 2024年第3期10卷 427-439页

作者： Ruiqing Tao hao tang wei yan Yading li Qianwen Mo ling li li Zhou Tao ma Jinbiao An Guoliang Xiao Xiucheng tan Southwest Petroleum University Division of Key Laboratory of Carbonate ReservoirsCNPCChengdu610500China Research Institute of Exploration and Development PetroChina Southwest Oil and Gas Field CompanyChengdu610051China Exploration Division PetroChina Southwest Oil and Gas Field CompanyChengdu610051China College of Geosciences China University of Petroleum(Beijing)Beijing102200China Chuanzhong Oil and Gas Geological Research Institute PetroChina Southwest Oil and Gas Field CompanySuining629000China

The Lower Ordovician Tongzi Formation containing abundant shoal sediments is the most promising stratum for the petroleum exploration in the Sichuan ***,the current studies mainly focus on the central part of the Basin,the systematic analysis of the southeastern part with well-developed shoal facies is *** paper aims to clarify the characteristics and genesis of the Tongzi Formation reservoir in Southeastern Sichuan Basin,following an analysis of sedimentary facies within the sequence stratigraphic *** research shows that the main types of reservoir rocks are oolitic,intraclastic and bioclastic *** the reservoir spaces consist mainly of intergranular(dissolved)pores,intercrystalline(dissolved)pores,intragranular dissolved pores and *** them,intergranular pores account for the highest proportion,which is followed by intragranular dissolved *** addition,most throats are necking and flaky which mainly connect intergranular and intercrystalline pores,*** diagenetic sequence shows that penecontemporaneous karst well improved the porosity of the reservoir in the early-stage although the cementation and compaction reduced parts of *** reservoir formation is associated with the tectonic-depositional settings,diageneses and terrigenous *** and submerged uplifts,forming in the early Ordovician amalgamation between yangtze and Cathaysia blocks,accumulated shoal sediments as the material basis for the reservoir *** karst forming intragranular dissolved pores and the dolomitization aiding grainstones to resist the pressure solution are the key to increasing porosity and preserving *** absence of terrigenous contamination prevented intergranular pores from being strongly cemented,which resulted in the reservoir difference between the central and southeastern Sichuan *** study can be used as a reference for the further exploration of Ordovician

关键词： Reservoir characteristics Reservoir genesis Tongzi formation Lower ordovician Southeastern Sichuan Basin

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