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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 577-585页

作者： Fanjing Meng Wenbo du Ning Ding Jian Sun xian du Ke Liu Shubo Li College of Materials Science and Engineering Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China

The hybrid of carbon nanotube(CNT)and reduced graphene oxide(RGO)reinforced ZK61 composite was fabricated by a hot extrusion process.Compared with the raw ZK61 alloy and single-reinforced composites,the hybrid-reinforced by RGO+CNT complex exhibited significant enhancements both in mechanical and thermal performance.By adjusting the proportion of RGO and CNT in ZK61 alloy,the obtained optimum ZK61/(0.06 wt%RGO+0.54 wt%CNT)composite exhibited increase of 25.4%in yield strength,26.5%in ultimate tensile strength,104%in failure strain and 30.4%in thermal conductivity,respectively,in comparison with ZK61 alloy.The superior properties of the nano-hybrid composite are attributed to the synergetic effects of RGO and CNT,leading to a uniform dispersion and integrated structure as well as the enhanced interfacial bonding with matrix.The strengthening ability of RGO and CNT was calculated to quantify their individual contribution to the improvement in mechanical and thermal properties of the ZK61 matrix composite.The RGO+CNT hybrids provide a promising way to develop Mg matrix composites with impressive performances.

关键词： Mg matrix composite Carbon nanotube Reduced graphene oxide Mechanical performance Thermal conductivity

Adaptive modification of turbofan engine nonlinear model based on LSTM neural networks and hybrid optimization method

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Chinese Journal of Aeronautics 2022年第9期35卷 314-332页

作者： Yanhua MA xian du Ximing SUN School of Microelectronics Dalian University of TechnologyDalian 116024China Key Laboratory of Intelligent Control and Optimization for Industrial Equipment Ministry of EducationDalian University of TechnologyDalian 116024China School of Control Science and Engineering Dalian University of TechnologyDalian 116024China

An accurate and reliable turbofan engine model which can describe its dynamic behavior within the full flight envelop and lifecycle plays a critical role in performance optimization, controller design and fault diagnosis. However, due to the performance differences caused by the tolerance of engine manufacturing and assembly, and performance degradation during continuously stringent environmental regulations, the model accuracy is severely reduced. In this paper, an adaptive modification method of turbofan engine nonlinear Component-Llevel Model(CLM) based on Long Short-Term Memory(LSTM) Neural Network(NN) and hybrid optimization algorithm is pro-posed. First, a dynamic compensator with a combined LSTM NN architecture is constructed to compensate for the initial error between the experimental data and CLM of a turbofan engine under health condition. Then, a sensitivity analysis approach based on the entropy coefficient and technique for order preference by similarity to an ideal solution integrated evaluation is developed to choose the unmeasurable health parameters to be adjusted. Finally, a parallel hybrid optimization algorithm is developed to complete the adaptive model modification when the performance degrades. The proposed method is verified on a military low-bypass twin-spool turbofan engine, and the experimental results show the effectiveness of the proposed method.

关键词： Hybrid optimization Long short-term memory Model modification and testing Sensitivity analysis Turbofan engines

Progress in processing of porous titanium: a review

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Rare Metals 2024年第5期43卷 1932-1955页

作者： Xiao-Li Yang xian-Feng du Zhi-Lin Xu Zhong-Shuai Liang Li-Long Xiong Engineering Research Center of Energy Storage Materials and Devices Ministry of Education School of Chemistry Xi'an Jiaotong University

As a novel structural and functional material,porous titanium and its alloys have been widely used in the aerospace, marine engineering and biomedical fields due to their high corrosion resistance, low density, good biocompatibility and excellent mechanical properties. Therefore, in this paper, a comprehensive review of powder metallurgy(PM)(including additive manufacturing(AM)processes) for fabricating porous titanium is firstly covered in terms of their working principles, capabilities, shortcomings and strengths. Simultaneously, the influencing factors of various methods on final pore structure of porous Ti are involved. Secondly, a summary of the chemical methods(CM) to obtain the porous Ti is also provided,such as dealloying method and reduction method. Finally,the tendency and direction of preparation technology as well as application of porous titanium were prospected.

关键词： Porous titanium Powder metallurgy Chemical method Pore structure Processing process

Simultaneously Enhanced Thermal and Mechanical Properties of ZK60 Alloy Reinforced by Oriented Graphene Nanoplatelets

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Acta Metallurgica Sinica(English Letters) 2023年第12期36卷 1999-2012页

作者： Baohong Zhu xian du Fanjing Meng Xuefeng Wu Ke Liu Shubo Li Zhaohui Wang Wenbo du Faculty of Materials and Manufacturing Beijing University of TechnologyBeijing100124China

The lamellar and orientational characteristics of graphene nanoplatelets(GNPs)are crucial for reinforcing metal matrix composites,particularly in terms of their thermal properties.Two kinds of GNPs with plane sizes of 6µm and 80µm were respectively used as reinforcements in ZK60 alloy by powder metallurgy.The oriented distribution of GNPs in the matrix was obtained using a double-pass hot extrusion process,i.e.,a stepped extrusion with two consecutive extrusion ratios(10:1 and 16:1).Reinforced with 0.05 wt%oriented GNPs(80µm),the composite exhibited a tensile yield strength of 257 MPa,ultimate tensile strength of 342 MPa,elongation of 24.7%,and notably enhanced thermal conductivity of 128.3 W(mK)−1 even with refined grain size compared to the ZK60 alloy.The oriented GNPs in the matrix create a favorable path for efficient load and heat transfer,leading to the simultaneously enhancement of mechanical and thermal properties of the GNPs/ZK60 composites.This work is expected to broaden the application potential of GNPs as highly efficient reinforcements and provide a practical method for fabricating metal matrix composites.

关键词： Graphene Magnesium Orientation Thermal properties Mechanical properties

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色味锁夸克物质与夸克星

物理学报 2024年第5期73卷 75-84页

作者：初鹏程刘鹤杜先斌青岛理工大学理学院青岛266033

讨论了零温、强磁场下基于准粒子模型的奇异夸克物质、色味锁夸克物质的热力学性质.结果表明色味锁夸克物质比奇异夸克物质更稳定,压强会随着色味锁态能隙常数的增大而增加.并且发现强磁场下磁星的最大质量会随着色味锁夸克物质的能隙... 详细信息

讨论了零温、强磁场下基于准粒子模型的奇异夸克物质、色味锁夸克物质的热力学性质.结果表明色味锁夸克物质比奇异夸克物质更稳定,压强会随着色味锁态能隙常数的增大而增加.并且发现强磁场下磁星的最大质量会随着色味锁夸克物质的能隙常数的增加而增加,磁星的潮汐形变率会随着能隙常数的增加而增加,磁星最大质量的中心密度会随着能隙常数的增加而降低.结果还说明考虑色味锁态得到的磁星质量半径关系可以满足最近实验观测PSR J0740+6620,PSR J0030+0451,和HESS J1731-347所给出的质量半径约束.

关键词：夸克物质夸克星磁星

Bibliometric analysis of soil phosphate solubilizing microorganisms research using VOSviewer

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Life Research 2024年第1期7卷 10-15页

作者： xian-yuan du Dan-dan Li Qiang-wei Wang Han-yu Zhang Yang Yang State Key Laboratory of Petroleum Pollutants Control China National Petroleum Corporation Research Institute of Safety and Environment TechnologyBeijing 102206China Department of Municipal and Environmental Engineering Hebei University of ArchitectureZhangjiakou 075000China College of Biological Science and Technology Shenyang Agricultural UniversityShenyang 110866China

Phosphorus-solubilizing microbes play key roles in improving phosphorus availability and in alleviating phosphorus nutrient limitation in soils. However, we did not have a comprehensive understanding of the overall research progress and development trend of phosphorus solubilizing microorganisms. In this study, we obtain documents from the Web of Science (WOS) core collection between 2002 and 2022, and a comprehensive review of the progress of global research on soil phosphate solubilizing microorganisms was conducted by using the VOSviewer bibliometric analysis tool. The results showed an increasing trend in the number of published articles from 2002 to 2022. India, accounting for 28% of the total number of published articles, became the most productive country. However, Canada was the country with the highest average citation frequency of articles. Chinese Academy of Sciences (CAS) was the greatest contributor with the most publications. Among the published journals, Frontiers in Microbiology, Applied Soil Ecology and Plant and Soil were the top three core journals in this field. Based on the keyword analysis, the assessment of the mechanisms between phosphorus solubilizing microbes and the soil carbon cycles with the different management practices became the new research trend among the scientific communities. These findings would provide an important reference value for future in-depth research on soil phosphate solubilizing microorganisms.

关键词： soil phosphate solubilizing microorganisms bibliometrics VOSviewe

Event-based triggering mechanisms for nonlinear control systems

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Science China(Information Sciences) 2020年第5期63卷 119-130页

作者： Yongfeng GAO Ximing SUN xian du Wei WANG Key Laboratory of Intelligent Control and Optimization for Industrial Equipment of Ministry of Education Dalian University of Technology

This study examines triggered implementations of stabilizing controllers for general nonlinear systems. By using perturbation theory and Taylor’s theorem, we propose new event-triggering and selftriggering mechanisms for general nonlinear control systems that are not necessarily input-to-state stable with respect to measurement errors. Both mechanisms are presented based on mild conditions and can ensure the uniform ultimate boundedness of the solutions of the resulting closed-loop control systems. The ultimate bounds can be made arbitrarily small by adjusting the design parameters. The effectiveness of the theoretical results is illustrated by simulations.

关键词： nonlinear systems triggered control sampled-data

Cooling rate controlled basal precipitates and age hardening response of solid-soluted Mg-Gd-Er-Zn-Zr alloy

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Journal of Magnesium and Alloys 2021年第4期9卷 1267-1277页

作者： Jinlong Fu Wenbo du Linyue Jia Yunfeng Wang Xunming Zhu xian du Faculty of Materials and Manufacturing Beijing University of TechnologyBeijing 100124China Weihai Wanfeng Magnesium S&T Development Co.LTD 264200China

The precipitation and age hardening response of the solid-soluted Mg–10Gd–1Er–1Zn–0.6Zr(wt.%)alloy performed by water-quenching(QC),air-cooling(AC)and furnace-cooling(FC)in terms of the volume fraction of precipitates and tensile properties were investigated in present paper.Results indicated the solid-soluted alloy contained stacking faults(SFs)and long period stacking ordered(LPSO)phase on the basal planes regardless of the cooling rate,but a larger volume fraction of the LPSO phase was formed with decreasing in the cooling rate.After aging,βandβ1 phases precipitated on the prismatic planes,and their number density decreased but mean particle size increased with decreasing in the cooling rate.The solid-soluted alloys(QC,AC and FC samples)showed no apparent difference in yield strength(YS),but their correspondent peak-aged alloys exhibited sharp difference in hardening response.The strongest hardening response took place in the QC sample and showed 82MPa enhancement in YS,which was much larger than that of AC(+26MPa)and FC samples(+5MPa).The reason lies in that the higher cooling rate promotes the precipitation and reduces the average size ofβprecipitate.A novel cooling-rate controlled precipitation model with respect to the correlation of precipitates on basal and prismatic planes was established.From this model,the basal precipitates showed a restrictive effect on the growth and/or coarsening ofβprecipitate,and composite precipitates containing theβphase with fine size as well as high area-number density and lower volume fraction of the LPSO phase are preferred to strengthen the Mg–10Gd–1Er–1Zn–0.6Zr alloy.

关键词： Magnesium alloy Long period stacking ordered(LPSO) Stacking faults(SFs) Cooling rate Tensile properties

结合GCN与LSTM的滚动轴承剩余寿命预测方法

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兰州理工大学学报 2024年第3期50卷 42-50页

作者：杜先君刘聪兰州理工大学电气工程与信息工程学院甘肃兰州730050

针对滚动轴承剩余寿命预测因振动信号的非线性和非平稳性而缺乏刻画健康状态可靠指标的问题,提出了将图卷积网络与长短期记忆网络结合的预测方法.首先,对轴承振动信号进行经验模态分解得到内涵模态分量,并且对内涵模态分量进行归一化处... 详细信息

针对滚动轴承剩余寿命预测因振动信号的非线性和非平稳性而缺乏刻画健康状态可靠指标的问题,提出了将图卷积网络与长短期记忆网络结合的预测方法.首先,对轴承振动信号进行经验模态分解得到内涵模态分量,并且对内涵模态分量进行归一化处理后计算邻接矩阵和特征矩阵;其次,将邻接矩阵和特征矩阵作为图卷积网络的输入,捕获数据关系,挖掘深层特征;然后,将深层特征和内涵模态分量输入长短期记忆网络从而实现时序关系建模,构建健康指标;最后,使用移动平均滤波消除振荡,对健康指标进行多项式拟合,并且计算达到阈值时刻,确定轴承剩余寿命.同时,以IEEE PHM 2012数据挑战赛数据集和XJTU-SY滚动轴承加速实验数据集为对象,验证所提方法.结果表明,使用图卷积网络与长短期记忆网络结合的模型构建健康指标进行滚动轴承剩余寿命预测时,预测结果能够较好地接近真实值,在实际应用中具有一定优势.

关键词：滚动轴承图卷积网络长短期记忆网络剩余寿命预测

Network Pharmacology of xian-Lian-Jie-du Decoction in Ameliorating Colorectal Cancer

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World Journal of Traditional Chinese Medicine 2024年第1期10卷 83-92页

作者： Ming-Xia Zhao Cheng-Lin Song Qin-Chang Zhang Hao-Jie du Shu-Qiong Zhang Yu-xian Shen Yang Sun Hai-Bo Cheng Wen Lv Department of Pharmacy School of Basic Medical SciencesAnhui Medical UniversityHefeiAnhuiChina Department of Biopharmaceutical Research Institute Anhui Medical UniversityHefeiAnhuiChina Department of Pharmaceutical Analysis State Key Laboratory of Natural and Biomimetic DrugsSchool of Pharmaceutical SciencesPeking UniversityBeijingChina Jiangsu Collaborative Innovation Center of Traditional Chinese Medicine in Prevention and Treatment of Tumor First Clinical CollegeNanjing University of Chinese MedicineNanjingJiangsuChina Deparment of Biotechnology and Pharmaceutical Sciences State Key Laboratory of Pharmaceutical BiotechnologySchool of Life SciencesNanjing UniversityNanjingJiangsuChina Deparment of Gynecology Institute of Traditional Chinese Medicine of Zhejiang ProvinceTongde Hospital of Zhejiang ProvinceHangzhouZhejiangChina

Objective:In this study,we screened for therapeutic targets of the xian-Lian-Jie-du decoction(XLJDD)for colorectal cancer(CRC)and explored the underlying mechanisms using network pharmacology techniques.Methods:Genes associated with CRC were collected from the Gene Cards database.The names of the active compounds of XLJDD were used as keywords in the“chemical name”in the Traditional Chinese Medicine Systems Pharmacology(TCMSP)database to search the targets.The protein-protein interaction(PPI)network was constructed using Cytoscape 3.8.1.Gene Ontology functional enrichment and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analyses were performed to identify key target proteins.Results:A total of 234 XLJDD-related targets and 250 cross-targets between XLJDD and CRC were collected based on the TCMSP and HIT 2.0 databases.A PPI network constructed based on the STRING database revealed interactions for all 250 proteins.The network results revealed TP53,MYC,CCND1,AKT1,CASP3,and STAT3 as core potential targets.KEGG pathway analysis of the 250 potential XLJDD targets for CRC in the Metascape database was performed using RStudio software.The top 12 gene ratio aggregated analysis results were visualized in bubble charts.The interleukin(IL)-17 signaling pathway had the highest correlation with the tumor necrosis factor(TNF)signaling pathway.Conclusions:XLJDD may be effective in ameliorating CRC by controlling inflammatory factors related to the IL-17 and TNF pathways and targeting proto-oncogenes and tumor suppressor genes,including MYC,CCND1,CTNNB1,and TP53.

关键词： Colorectal cancer network pharmacology xian-Lian-Jie-du decoction