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A parametric study on unbalanced moment of piston type valve core

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2021年第4期22卷 265-276页

作者： Jin-yuan QIAN Juan MU cong-wei hou Zhi-jiang JIN Institute of Process Equipment College of Energy EngineeringZhejiang UniversityHangzhou 310027China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China

In this paper,the piston type valve core and the unbalanced moment on its bottom are *** decrease the influence of non-common geometrical factors,a simplified model of the piston type globe valve is proposed in this *** on the computational fluid dynamics(CFD)method,the effects of different geometrical parameters on the unbalanced moment existing on the bottom of the valve core,which include the bending radius of the inlet flow channel,the diameter of the special-shaped pipe,and the height of the valve core,are ***,the effects of geometrical parameters on the unbalanced moment on the bottom of the valve core are clarified by correction and variation classification and provide a basis for further optimizing the structure of the piston type *** results show that the unbalanced moment decreases with the increase of the bending radius of the inlet flow channel,but increases with the increase of the diameter of the special-shaped pipe and the height of the valve ***,the relation between the unbalanced moment and flow rate is proposed.

关键词： Piston type valve core Unbalanced moment Geometrical parameters Computational fluid dynamics(CFD)

基于“实践取向”的学前教育本科应用型人才培养模式研究

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长春师范大学学报 2017年第9期36卷 169-171页

作者：于聪侯伟新长春师范大学初等教育学院吉林长春130031

应用型本科教育既具有高等教育的属性,又具有职业教育的实践属性。学前教育专业在应用型人才培养模式上要以实践为导向,通过成立"三方协作"实践共同体,转变人才培养定位、调整课程设置、变革教学及评价方式,探索出学前教育本科应用型人... 详细信息

应用型本科教育既具有高等教育的属性,又具有职业教育的实践属性。学前教育专业在应用型人才培养模式上要以实践为导向,通过成立"三方协作"实践共同体,转变人才培养定位、调整课程设置、变革教学及评价方式,探索出学前教育本科应用型人才培养的特色发展路径。

关键词：实践取向学前教育应用型本科人才培养模式

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ADN在Pd-Zn体系中的催化分解研究

化学工程 2017年第7期45卷 61-64,73页

作者：鹿小林丛伟民侯宝林朱少敏王晓东大连交通大学材料科学与工程学院辽宁大连116028 中国科学院大连化学物理研究所辽宁大连116028

二硝酰胺铵(ADN)是一种无毒高比冲的单组元推进剂。实现ADN水溶液的高效催化分解对于推力器启动和产生稳定推力起着至关重要的作用。文中采用浸渍法制得不同质量比(10∶0.2,10∶1,10∶5)的Pd-Zn/Al_2O_3双金属催化剂。利用TGA-DTA和MS-o... 详细信息

二硝酰胺铵(ADN)是一种无毒高比冲的单组元推进剂。实现ADN水溶液的高效催化分解对于推力器启动和产生稳定推力起着至关重要的作用。文中采用浸渍法制得不同质量比(10∶0.2,10∶1,10∶5)的Pd-Zn/Al_2O_3双金属催化剂。利用TGA-DTA和MS-online对相关的催化分解动力学和反应机理进行了研究,同时使用TEM等对催化剂形貌进行了表征。结果表明,Pd-Zn/Al_2O_3双金属催化剂能够实现ADN的一步分解,微量Zn的加入能起到稳定和分散金属Pd的作用。当Pd和Zn的质量比为10∶0.2时,催化剂具有良好催化活性和稳定性,并且使二硝酰胺铵(ADN)催化分解向生成较高N_2含量的方向进行。

关键词： Pd-Zn双金属催化剂单组元推进剂 ADN催化分解无毒

Multi-layer multi-pass friction rolling additive manufacturing of Al alloy:Toward complex large-scale high-performance components

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 425-438页

作者： Haibin Liu Run hou Chenghao Wu Ruishan Xie Shujun Chen College of Mechanical&Energy Engineering Beijing University of TechnologyBeijing 100124China Chongqing Research Institute of Beijing University of Technology Chongqing 401121China

At present,the emerging solid-phase friction-based additive manufacturing technology,including friction rolling additive man-ufacturing(FRAM),can only manufacture simple single-pass *** this study,multi-layer multi-pass FRAM-deposited alumin-um alloy samples were successfully prepared using a non-shoulder tool *** material flow behavior and microstructure of the over-lapped zone between adjacent layers and passes during multi-layer multi-pass FRAM deposition were studied using the hybrid 6061 and 5052 aluminum *** results showed that a mechanical interlocking structure was formed between the adjacent layers and the adja-cent passes in the overlapped center *** friction and rolling of the tool head led to different degrees of lateral flow and plastic deformation of the materials in the overlapped zone,which made the recrystallization degree in the left and right edge zones of the over-lapped zone the highest,followed by the overlapped center zone and the non-overlapped *** tensile strength of the overlapped zone exceeded 90%of that of the single-pass deposition *** is proved that although there are uneven grooves on the surface of the over-lapping area during multi-layer and multi-pass deposition,they can be filled by the flow of materials during the deposition of the next lay-er,thus ensuring the dense microstructure and excellent mechanical properties of the overlapping *** multi-layer multi-pass FRAM deposition overcomes the limitation of deposition width and lays the foundation for the future deposition of large-scale high-performance components.

关键词： aluminum alloy additive manufacturing solid-state friction stir welding multi-layer multi-pass

The best of both worlds:cicada males change costly signals to achieve mates while females choose a mate based on both calling and courtship songs

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Current Zoology 2022年第6期68卷 716-725页

作者： Zehai hou Songshan wei cong wei Key Laboratory of Plant Protection Resources and Pest Management of the Ministry of Education College of Plant ProtectionNorthwest A&F UniversityYanglingShaanxi 712100China Beijing Key Laboratory for Forest Pest Control Beijing Forestry UniversityBeijing 100083China

Cicadas usually sing and mate in the higher parts of *** addressing the effects of different acoustic signals on mate choice in Cicadidae are very *** investigated the effects of both acoustical features and morphological traits on mate choice in an East Asian cicada Platypleura *** produce high-rate calling songs that attract females,then produce low-rate courtship songs to secure mating when a female is *** calling song rate(CR),shorter single-pulse duration,and shorter pulse period of the calling song,together with lower courtship song rate and longer echeme period of the courtship song,are the most desirable traits used by females to choose a *** traits indicate that the more amale can raise the rate of song production,the higher the probability he is sexually selected by the *** correlation was found between morphological traits and mating *** mating,a minority of males started emitting calling songs again,but the CR was significantly lower than before mating and none of them attracted a new mate *** promotes females mating with unmated *** hypothesize that *** may have the best of both worlds due to the unique song modulation and the mechanism of female mate choice:males change energetically,costly acoustic signals to achieve mates,while females choose a mate based on males’acoustic *** results contribute to better understanding the diversity of mating preference and enrich the mechanism of mate choice in acoustic insects.

关键词： acoustic insects Cicadidae courtship mate choice song modulation

Females prefer males producing a high-rate song with shorter timbal-stridulatory sound intervals in a cicada species

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Current Zoology 2022年第1期68卷 103-112页

作者： Zehai hou Yunxiang LIU Songshan wei cong wei Key Laboratory of Plant Protection Resources and Pest Management of the Ministry of Education College of Plant ProtectionNorthwest A&F UniversityYanglingShaanxi 712100China Beijing Key Laboratory for Forest Pest Control College of ForestryBeijing Forestry UniversityBeijing 100083China

Uncovering mate choice and factors that lead to the choice are very important to understanding sexual selection in evolutionary *** are known for their loud sounds produced by males using the ***,males in certain cicada species emit 2 kinds of sounds using respectively timbals and stridulatory organs,and females may produce their own sounds to respond to *** has never been considered is the mate choice in such cicada ***,we investigate the sexual selection and potential impact of predation pressure on mate choice in the cicada Subpsaltria yangi *** possesses stridulatory sound-producing organs in both sexes in addition to the timbals in *** show that males producing calling songs with shorter timbal–stridulatory sound intervals and a higher call rate achieved greater mating *** morphological traits were found to be correlated with mating success in both sexes,suggesting neither males nor females display mate preference for the opposite sex based on morphological *** do not discriminate among responding females during mate searching,which may be due to the high energy costs associated with their unusual mate-seeking activity and the male-biased predation *** generally mate once but a minority of them re-mated after oviposition which,combined with the desirable acoustic traits of males,suggest females may maximize their reproductive success by choosing a high-quality male in the first *** study contributes to our understanding mechanisms of sexual selection in cicadas and other insects suffering selective pressure from predators.

关键词： Cicadidae female choice mating success predation pressure sexual selection.

Multi-model ensemble learning for battery state-of-health estimation:Recent advances and perspectives

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Journal of Energy Chemistry 2025年第1期100卷 739-759页

作者： Chuanping Lin Jun Xu Delong Jiang Jiayang hou Ying Liang Zhongyue Zou Xuesong Mei State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong University Shaanxi Key Laboratory of Intelligent Robots School of Mechanical Engineering Xi'an Jiaotong University Department of Electrical Engineering and Automation Luoyang Institute of Science and Technology School of Mechanical Engineering Hangzhou Dianzi University

The burgeoning market for lithium-ion batteries has stimulated a growing need for more reliable battery performance monitoring. Accurate state-of-health(SOH) estimation is critical for ensuring battery operational performance. Despite numerous data-driven methods reported in existing research for battery SOH estimation, these methods often exhibit inconsistent performance across different application scenarios. To address this issue and overcome the performance limitations of individual data-driven models,integrating multiple models for SOH estimation has received considerable attention. Ensemble learning(EL) typically leverages the strengths of multiple base models to achieve more robust and accurate outputs. However, the lack of a clear review of current research hinders the further development of ensemble methods in SOH estimation. Therefore, this paper comprehensively reviews multi-model ensemble learning methods for battery SOH estimation. First, existing ensemble methods are systematically categorized into 6 classes based on their combination strategies. Different realizations and underlying connections are meticulously analyzed for each category of EL methods, highlighting distinctions, innovations, and typical applications. Subsequently, these ensemble methods are comprehensively compared in terms of base models, combination strategies, and publication trends. Evaluations across 6 dimensions underscore the outstanding performance of stacking-based ensemble methods. Following this, these ensemble methods are further inspected from the perspectives of weighted ensemble and diversity, aiming to inspire potential approaches for enhancing ensemble performance. Moreover, addressing challenges such as base model selection, measuring model robustness and uncertainty, and interpretability of ensemble models in practical applications is emphasized. Finally, future research prospects are outlined, specifically noting that deep learning ensemble is poised to advance ens

关键词： Lithium-ion battery State-of-health estimation Data-driven Machine learning Ensemble learning Ensemble diversity

Practical approach for detecting k-nonseparability of multipartite quantum states

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 32-48页

作者： Jie Guo Jinchuan hou Xiaofei Qi Kan He College of Mathematics Taiyuan University of Technology School of Mathematics and Statistics Shanxi University Key Laboratory of Complex Systems and Data Science of Ministry of Education Shanxi University

The instantaneous detection of entanglement in quantum states poses a significant challenge in the fields of quantum computation and quantum information, and there are no practical methods or tools to complete this task satisfactorily so far. We propose a sufficient and necessary criterion of k-nonseparability for any n-partite finite or infinite dimensional systems, 2 ≤ k ≤ n. This criterion serves as the foundation for a practical scheme designed to detect entanglement and k-nonseparability across multipartite finite-dimensional systems. To exemplify the application of our scheme, we have developed a software tool that facilitates swift and precise identification of entanglement, k-nonseparability, and genuine entanglement within n-qubit systems, specifically tailored for systems with 2 ≤ n ≤ 4.

关键词： multipartite systems entanglement states entanglement witnesses ${\bm~k}$-nonseparability

Low-temperature chlorination roasting technology for the simultaneous recovery of valuable metals from spent LiCoO_(2)cathode material

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 80-91页

作者： Junjie Shi Changle hou Jingjing Dong Dong Chen Jianzhong Li Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China

With the continuous increase in the disposal volume of spent lithium-ion batteries(LIBs),properly recycling spent LIBs has become essential for the advancement of the circular *** study presents a systematic analysis of the chlorination roasting kinetics and proposes a new two-step chlorination roasting process that integrates thermodynamics for the recycling of LIB cathode *** activation energy for the chloride reaction was 88.41 kJ/mol according to thermogravimetric analysis–derivative thermogravimetry data obtained by using model-free,model-fitting,and Z(α)function(αis conversion rate).Results indicated that the reaction was dominated by the first-order(F1)model when the conversion rate was less than or equal to 0.5 and shifted to the second-order(F2)model when the conversion rate exceeded *** conditions were determined by thoroughly investigating the effects of roasting temperature,roasting time,and the mass ratio of NH_(4)Cl to LiCoO_(2).Under the optimal conditions,namely 400℃,20 min,and NH_(4)Cl/LiCoO_(2)mass ratio of 3:1,the leaching efficiency of Li and Co reached 99.43% and 99.05%,*** of the roasted products revealed that valuable metals in LiCoO_(2)transformed into CoCl_(2) and ***,the reaction mechanism was elucidated,providing insights for the establishment of a novel low-temperature chlorination roasting technology based on a crystal structure *** technology can guide the development of LIB recycling processes with low energy consumption,low secondary pollution,high recovery efficiency,and high added value.

关键词： spent lithium-ion battery thermodynamics chlorination roasting kinetics circular economy