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RESEARCH ON INFLUENCE OF tEMPERAtURE ON A PRECISION FORGING PROCESS OF BLADE WItH A tENON

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Acta Metallurgica Sinica(English Letters) 2005年第6期18卷 749-755页

作者： y.L. Liu H. yang t. Gao M. Zhan W. Cai College of Materials Science and Engineering Northwestern Polytechnical University Xi＇an 710072 China

the blade precision forging process is a forming process with high temperature and large plastic deformation. Interaction of deformation and heat conduction leads to large uneven distribution of temperature. the unevenness of temperature distribution has a great effect on mechanical properties and the microstracture of materials. So it is necessary to consider the influence of temperature on the precision forging process of blades. taking a blade with a tenon into consideration, a 3D mechanical model in precision forging is built up. the distribution laws of temperature field and the influence of the temperature on the equivalem stress in the process are obtained by using 3-D coupled thermo-mechanical FEM code developed by the authors theresuits obtained illustrate that the influence of the temperature field on the blade forging process is considerable. the achievements of predicting microstructure and mechanical properties for forged blades is significant.

关键词： blade with a tenon precision forging equivalent stress field,temperature field thermo-mechanical coupled 3D FEM simulation

Universal design of three-dimensional porous graphene-iron based promotors for kinetically rationalized lithium-sulfur chemistry

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Journal of Energy Chemistry 2025年第1期100卷 192-200页

作者： Hua Gao yunfeng Zhang Menglei Wang Ruoxuan yang Shuai Feng Xuan Cao yaping Zhang Zhongyuan Lu yingze Song State Key Laboratory of Environment-Friendly Energy Materials School of Materials and Chemistry Southwest University of Science and Technology School of Material Science and Engineering Henan University of Technology College of Chemistry and Chemical Engineering Taishan University

Lithium-sulfur （Li-S） batteries are widely deemed to be one of the most potential candidates for future secondary batteries because of their remarkable energy ***,notorious polysulfide shuttling and retarded sulfur reaction kinetics pose significant obstacles to the further application of Li-S *** rationally designed highly active electrocatalysts can facilitate polysulfide conversion,the universal and scalable synthesis strategies need to be ***,a universal synthetic strategy to construct a series of three-dimensional （3D） porous graphene-iron （3DGr-Fe） based electrocatalysts involving 3DGr-FeP,3DGr-Fe3C,and 3DGr-Fe3Se4is exploited for manipulating the Li-S redox *** has been observed that the implementation of a 3D porous Gr architecture leads to the well-designed conductive networks,while the uniformly dispersed iron nanoparticles introduce an abundance of active sites,fostering the lithium polysulfide conversion,thereby bolstering the overall electrochemical *** Li-S battery with the 3DGr-Fe based electrocatalyst exhibits remarkable capacity retention of 94.8%upon 100 times at 0.2 ***,the soft-packaged Li-S pouch cell based on such a 3DGr-Fe electrocatalyst delivers superior capacity of 1060.71 mA h g-1and guarantees for the continuous 30 min work of fan *** investigation gives comprehensive insights into the design,synthesis,and mechanism of 3DGr-Fe based electrocatalysts with high activity toward efficient and durable Li-S batteries.

关键词： Lithium-sulfur battery Universal synthesis 3D graphene-iron based promotor Electrocatalysis

Ru团簇对Ni/Ni_(3)Al合金纳米线形变影响的原子模拟

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原子与分子物理学报 2025年第1期42卷 81-87页

作者：阳喜元岭南师范学院物理科学与技术学院湛江524048

镍基高温合金是制造先进航空发动机热端部件的关键材料之一,其高温力学性能直接关系到发动机运行安全和使用寿命.本文采用改进分析型嵌入原子模型(MAEAM)和分子动力学(MD)研究合金化元素钌(Ru)团簇对Ni/Ni_(3)Al纳米线形变机制的影响,... 详细信息

镍基高温合金是制造先进航空发动机热端部件的关键材料之一,其高温力学性能直接关系到发动机运行安全和使用寿命.本文采用改进分析型嵌入原子模型(MAEAM)和分子动力学(MD)研究合金化元素钌(Ru)团簇对Ni/Ni_(3)Al纳米线形变机制的影响,结果表明:在单轴拉伸应变下,纳米线的弹性模量和屈服强度随温度升高而降低.温度较低时,纳米线形变由位错产生与发射而导致晶格滑移所引起.由于晶格热振动非谐效应不明显,Ru团簇阻碍效果显著,使得晶格滑移区域仅限于Ru团簇与Ni/Ni_(3)Al相界面之间且呈非对称分布.温度较高时,纳米线的形变由位错发射而引起晶格滑移所致,但因非谐效应显著,Ru团簇无法阻碍位错运动,滑移区域在Ru团簇周围对称分布于Ni_(3)Al相中.最后从Ru团簇微观结构及其稳定性的角度进一步分析其对纳米线形变影响.

关键词： Ru团簇形变机制 Ni/Ni_(3)Al纳米线原子模拟

Hydrogen-bonded organic framework-ionic liquid composite quasisolid electrolyte for high-performance lithium battery

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Nano Research 2025年第1期18卷 332-340页

作者： Junmei Zhang yatao Wu Chenye Wang yong Liu Zhirong yang Shiyue Zhou Wenpeng Li Wenjia Wu Jingtao Wang School of Chemical Engineering Zhengzhou UniversityZhengzhou 450001China

Ionic liquids(ILs)hold great promise as highperformance electrolyte material due to their unique advantages including nonvolatility,high thermal stability and high ionic ***,the IL-based electrolytes always suffer from serious ion aggregation and high viscosity at low temperatures,leading to significantly decline in ionic ***,hydrogen-bonded organic framework-ionic liquid composite quasi-solid electrolyte(high temperature treatment(Ht)-HOF-IL CQSE)was prepared through confining the IL electrolytes(ILEs)into the pore of HOF lamellar *** weak hydrogen bonding interactions within HOF nanosheets,together with the generated interactions between ILE and HOF,enable uniform and continuous distribution of ILE in HOF lamellar *** effectively inhibits the ion migration of ILE,which meanwhile serves as Li+transfer sites,affording high ionic conductivity of 5.7×10^(-5)S·cm-1 at-60 ℃,with high lithium-ion transference number of 0.69,whereas ILEs usually lose ionic conduction ability at such low *** assembled Li symmetrical cell can stably cycle at 0.2 mA·cm^(-2)and^(-2)0 ℃ for more than 1500 *** LiFePO_(4)|Ht-HOF-IL CQSE|Li cell shows excellent cycling performance at 0.5 C at a wide temperature range of^(-2)0 to 60 ℃.this work may pave a new avenue for the development of high-performance IL-based composite electrolytes.

关键词： ionic liquid hydrogen-bonded organic framework low-temperature ionic conductivity lithium-ion transference number quasi-solid electrolyte

Atomically precise nickel-sulfur clusters for efficient electrochemical 2,5-hydroxymethylfurfural oxidation

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Nano Research 2025年第1期18卷 140-148页

作者： Fen Wang Lu-yu Liu Sha-Sha Cui ting-ting Li Xiao-Meng yang Zhijuan Liu yanyong Wang Henan Key Laboratory of Crystalline Molecular Functional Materials Henan International Joint Laboratory of Tumor Theranostical Cluster MaterialsGreen Catalysis Centerand College of ChemistryZhengzhou UniversityZhengzhou 450001China State Key Laboratory of Chem/Bio-sensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China

Nickel sulfide exhibits excellent catalytic activity in the electrochemical 2,5-hydroxymethylfurfural oxidation reaction(HMFOR).However,due to the polydispersity of nanoparticles,it is difficult to establish a clear structure-activity relationship at the atomic *** this work,we have successfully synthesized atomically precise Ni_(6)(PEt)_(12)and Ni_(4)(PEt)_(8)clusters(PEt:2-phenylethanethiol)for ***^(2+)and S_(2)-with atomic ratio of 1:2 was mainly existed in Ni_(6)(PEt)_(12)and Ni_(4)(PEt)_(8)to form Ni-S *** electrochemical test results have suggested both Ni_(6)(PEt)_(12)and Ni_(4)(PEt)_(8)displayed outstanding electrocatalytic ability for *** Ni_(6)(PEt)_(12)exhibited better electrocatalytic ability than Ni_(4)(PEt)_(8)with higher current density,lower overpotential and faster reaction *** superior electrochemical ability of Ni_(6)(PEt)_(12)may be due to the enhanced adsorption towards HMF molecule with strong interaction towards hydroxyl group and furan ***,it found that the Ni^(2+)species in Ni_(6)(PEt)_(12)could rapidly oxidized into Ni^(3+)species,which could spontaneously capture electron and proton from HMF for *** theoretical calculation demonstrated that the Ni_(6)(PEt)_(12)process lower free energy barrier than Ni_(4)(PEt)_(8)to display excellent electrocatalytic *** work is of great significance for designing efficient electrocatalysts for HMFOR.

关键词： atomically precise nickel nanoclusters 2 5-hydroxymethylfurfural electro-oxidation Ni3+species

基于图像处理和BP神经网络的森林防火无人机系统

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农机化研究 2025年第2期47卷 205-209页

作者：杨静湖北警官学院武汉430034

对无人机设计方案、图像处理和火焰分割算法的技术原理进行了介绍,并利用BP神经网络对图像中的火焰面积变化率和火焰尖角等特征进行识别,实现了对森林火灾的快速监测。实验结果表明:系统的准确率为98.5%,比普通神经网络的84.5%更高;耗时... 详细信息

对无人机设计方案、图像处理和火焰分割算法的技术原理进行了介绍,并利用BP神经网络对图像中的火焰面积变化率和火焰尖角等特征进行识别,实现了对森林火灾的快速监测。实验结果表明:系统的准确率为98.5%,比普通神经网络的84.5%更高;耗时仅22 s,比普通神经网络159 s缩短很多。这表明,BP神经网络是更可靠且更有效率的火灾识别方案。

关键词：森林防火无人机图像处理 BP神经网络

Parameter Optimisation of Stress-strain Constitutive Equations Using Genetic Algorithms

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Journal of Materials Science & technology 2003年第Z1期19卷 5-8页

作者： y. y. yang M. Mahfouf D.A.Linkens Department of Automatic Control and Systems Engineering University of Sheffield Mappin St. Sheffield S1 3JD UK Department of Automatic Control and Systems Engineering University of Sheffield Mappin St. Sheffield S1 3JD UK Department of Automatic Control and Systems Engineering University of Sheffield Mappin St. Sheffield S1 3JD UK

the accuracy of numerical simulations and many other material design calculations, such as the rolling force, rollingtorque, etc., depends on the description of stress-strain relationship of the deformed materials. One common methodof describing the stress-strain relationship is using constitutive equations, with the unknown parameters fitted byexperimental data obtained via plane strain compression (PSC). Due to the highly nonlinear behaviour of the constitutive equations and the noise included in the PSC data, determination of the model parameters is difficult. Inthis paper, genetic algorithms were exploited to optimise parameters for the constitutive equations based on thePSC data. the original PSC data were processed to generate the stress-strain data, and data pre-processing wascarried out to remove the noise contained in the original PSC data. Several genetic optimisation schemes have beeninvestigated, with different coding schemes and different genetic operators for selection, crossover and *** was found that the real value coded genetic algorithms converged much faster and were more efficient for theparameter optimisation problem.

关键词： Genetic algorithms, Parameter optimisa tion, Aluminium alloy, Flow stress, Constitutive equations

PCA-BP神经网络模型在拖拉机发动机故障诊断中的应用

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农机化研究 2025年第3期47卷 254-258页

作者：杨健成都农业科技职业学院成都611130

拖拉机发动机故障诊断是指通过对拖拉机发动机的运行状态、传感器数据等信息进行分析和处理,识别出发动机故障的类型和位置,及时准确地诊断拖拉机发动机故障,对于提高农机装备的使用效率和经济效益具有重要的意义。为此,基于主成分分析(... 详细信息

拖拉机发动机故障诊断是指通过对拖拉机发动机的运行状态、传感器数据等信息进行分析和处理,识别出发动机故障的类型和位置,及时准确地诊断拖拉机发动机故障,对于提高农机装备的使用效率和经济效益具有重要的意义。为此,基于主成分分析(PCA)算法对拖拉机发动机的传感器数据进行降维处理,并使用BP神经网络对降维后的数据进行分类识别,以实现拖拉机发动机故障的诊断。试验结果表明:PCA-BP神经网络模型可以准确地诊断拖拉机发动机的多种故障,相比于传统的BP神经网络模型,具有更高的准确率和更好的泛化能力,表明PCA-BP神经网络模型在拖拉机发动机故障诊断中具有较大的应用前景。

关键词：拖拉机发动机故障诊断主成分分析 BP神经网络

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Reduced mesencephalic astrocyte-derived neurotrophic factor expression by mutant androgen receptor contributes to neurodegeneration in a model of spinal and bulbar muscular atrophy pathology

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Neural Regeneration Research 2025年第9期20卷 2655-2666页

作者： yiyang Qin Wenzhen Zhu tingting Guo yiran Zhang tingting Xing Peng yin Shihua Li Xiao-Jiang Li Su yang Guangdong Key Laboratory of Non-human Primate Research Key Laboratory of CNS Regeneration(Ministry of Education)Guangdong–HongKong–Macao Institute of CNS RegenerationJinan UniversityGuangzhouGuangdong ProvinceChina

Spinal and bulbar muscular atrophy is a neurodegenerative disease caused by extended CAG trinucleotide repeats in the androgen receptor gene,which encodes a ligand-dependent transcription facto *** mutant androgen receptor protein,characterized by polyglutamine expansion,is prone to misfolding and forms aggregates in both the nucleus and cytoplasm in the brain in spinal and bulbar muscular atrophy *** aggregates alter protein-protein interactions and compromise transcriptional *** this study,we reported that in both cultured N2a cells and mouse brain,mutant androgen receptor with polyglutamine expansion causes reduced expression of mesencephalic astrocyte-de rived neurotrophic *** n of mesencephalic astrocyte-derived neurotrophic factor amelio rated the neurotoxicity of mutant androgen receptor through the inhibition of mutant androgen receptor *** down endogenous mesencephalic astrocyte-derived neurotrophic factor in the mouse brain exacerbated neuronal damage and mutant androgen receptor *** findings suggest that inhibition of mesencephalic astrocyte-derived neurotrophic factor expression by mutant androgen receptor is a potential mechanism underlying neurodegeneration in spinal and bulbar muscular atrophy.

关键词： androgen receptor mesencephalic astrocyte-derived neurotrophic factor mouse model neurodegeneration neuronal loss neurotrophic factor polyglutamine disease protein misfolding spinal and bulbar muscular atrophy transcription factor