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第八届国际振动工程会议

作者： Hao Ying du xuwen Wu Zhiqiang Department of College of Civil Engineering & Mechanics Yan Shan University Department of School of Mechanical Engineering TianJin University

In this paper, the stochastic-aeroelastic nonlinear response of a three-degree-of-freedom(3-Dof), structural nonlinear airfoil with a control flap is presented. The critical parameter conditions of stochastic P-bifurcation are solved by using the improved average method, the stochastic average method combined with the singularity theory. The results show that the periodic solution produced by Hopf bifurcation has involved a second bifurcation, the nonlinear critical speed of saddle node bifurcation points is advanced, and the airfoil appears bi-stable. The stochastic singularity analysis shows that the increasing in stochastic disturbance intensity will cause an greater of the probability for large amplitude stochastic flutter.

关键词： Stochastic P-bifurcation of a 3-Dof Airfoil with Stochastic parametric excitation

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科技金融与科技创新协同发展研究——以陕西省为例

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商展经济 2021年第14期 84-86页

作者：杜旭雯西安外国语大学商学院

科技创新和科技金融是促进国民经济提升的两大引擎。本文以陕西省为例,通过建立协同度模型来观测科技金融与科技创新复合系统的协同发展态势,并运用DEA方法测算二者协同发展的绩效,对其作出评价。结果表明,陕西省科技金融与科技创新子... 详细信息

科技创新和科技金融是促进国民经济提升的两大引擎。本文以陕西省为例,通过建立协同度模型来观测科技金融与科技创新复合系统的协同发展态势,并运用DEA方法测算二者协同发展的绩效,对其作出评价。结果表明,陕西省科技金融与科技创新子系统有序度的变化趋势较为一致,呈上升态势,但其复合系统整体协同度较低,在[0,0.2]区间波动,可见陕西省还没有建立起一个良性的科技金融与科技创新协同发展机制。为此,政府应加快推进科技金融与科技创新资源的有效对接,强化动态协同匹配,以提升陕西省科技金融与科技创新复合系统整体协同绩效。

关键词：科技金融科技创新协同发展 DEA 陕西省

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大倾角煤层回采巷道支护方案设计

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能源与节能 2020年第9期 109-110页

作者：杜旭文霍州煤电集团金能煤业有限公司山西静乐035100

针对大倾角煤层回采巷道支护难度大、支护效果差的问题,在分析锚杆支护理论和锚杆支护可靠性的基础上,分析了大倾角煤层回采巷道矿压显现规律和锚杆支护在大倾角煤层巷道支护的可行性。最后,根据煤矿地质条件及煤层特点确定了巷道顶板... 详细信息

针对大倾角煤层回采巷道支护难度大、支护效果差的问题,在分析锚杆支护理论和锚杆支护可靠性的基础上,分析了大倾角煤层回采巷道矿压显现规律和锚杆支护在大倾角煤层巷道支护的可行性。最后,根据煤矿地质条件及煤层特点确定了巷道顶板、两帮及底板的支护参数。

关键词：大倾角锚杆锚索巷道支护

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煤矿锚杆(索)支护参数设计及效果监测

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机械管理开发 2020年第5期35卷 10-11,52页

作者：杜旭文霍州煤电集团金能煤业有限公司山西忻州035100

针对工作面巷道支护效果不佳或者支护过度导致支护成本高的问题,以某煤矿3号煤层工作面为研究对象,在分析其顶底板、煤层特点情况的基础上,分析了锚杆(索)联合支护的机理,并搭建模型验证所设计支护参数下的顶底板变形及应力情况,经试验... 详细信息

针对工作面巷道支护效果不佳或者支护过度导致支护成本高的问题,以某煤矿3号煤层工作面为研究对象,在分析其顶底板、煤层特点情况的基础上,分析了锚杆(索)联合支护的机理,并搭建模型验证所设计支护参数下的顶底板变形及应力情况,经试验应用发现锚杆(索)联合支护能够起到恰当的支护效果。

关键词：锚杆锚索联合支护耦合支护安全生产

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Yonarolide A, an unprecedented furanobutenolide-containing norcembranoid derivative formed by photoinduced intramolecular[2+2] cycloaddition

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Chinese Chemical Letters 2023年第2期34卷 420-424页

作者： Yeqing du Ligong Yao xuwen Li Yuewei Guo School of Chinese Materia Medica Nanjing University of Chinese MedicineNanjing 210023China State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China Drug Discovery Shandong Laboratory Bohai Rim Advanced Research Institute for Drug DiscoveryYantai 264117China

Eight polycyclic furanobutenolide-containing norcembrane diterpenoids featuring C19 frameworks(1–8)were rapidly recognized and isolated from the Hainan soft coral Sinularia sp. by the HSQC-based small molecule accurate recognition technology. Yonarolide A(1a), featuring an unprecedented 5/6/4/4/7 pentacyclic ring skeleton, was surprisingly obtained as a transformed product by leaving compound 1 under indoor natural light, and was further proved to be a [2 + 2] cycloaddition product of 1 by photochemical reaction. The absolute stereochemistry of 1a and the three known norcembrane diterpenoids 1, 4, and7 were determined by using X-ray diffraction(XRD) analyses. Further, with the aid of XRD analysis, the structure of scabrolide B(2), which was previously reported of possessing 5/6/7 tricyclic skeleton, was firmly revised as 2a with the rare inelegane skeleton featured by the highly oxygenated 5/7/6 tricyclic carbocycle.

关键词： Soft coral Sinularia Norcembranoid Photocycloaddition SMART method

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Multi-objective optimization of concave radial forging process parameters based on response surface methodology and genetic algorithm

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INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY 2024年第9-10期130卷 5025-5044页

作者： du, Zun Xu, Wenxia Wang, Zhaohui Zhu, xuwen Wang, Junshi Wang, Hongxia Wuhan Univ Technol Wuhan University of Technology Hubei Longzhong Lab Xiangyang 441000 Hubei Peoples R China Wuhan Univ Sci & Technol Key Lab Met Equipment & Control Technol Minist Educ Wuhan 430081 Hubei Peoples R China Wuhan Univ Sci & Technol Hubei Key Lab Mech Transmiss & Mfg Engn Wuhan 430081 Hubei Peoples R China Hubei Univ Automot Technol Coll Mech Engn Shiyan 442002 Peoples R China

To enhance the forming quality of the forging and minimize the forging cost in the concave radial forging process, this article examines the influence of process parameters (radial reduction increment h, rotation angle beta, friction coefficient mu) on the forging process through numerical simulation. A multi-objective optimization method is employed to balance the objective functions (strain homogeneity E, forging load F). First, sample points for different combinations of process parameters were obtained using a central composite experimental design. Then, a mathematical model between the process parameters and the objective function was established using the response surface method, which underwent variance analysis and sensitivity analysis. Finally, the optimal process parameter combination was determined based on the NSGA-II algorithm and satisfaction function. The optimization results were verified by finite element simulations. The optimized process combination: increment h = 0.25 mm, beta = 21.68 degrees, mu = 0.05. The corresponding E and F are 0.241367 and 577.029, respectively. Compared with the initial process, the standard deviation of the overall strain was reduced by 14.25%, and the forging load was reduced by 1.76%. The results indicate that the quality of the forgings was significantly improved while the forging cost was reduced to some extent.

关键词： Concave radial forging Process parameters Multi-objective optimization Strain homogeneity Forging load

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Transient Stability Evaluation of Independent Microgrid based on Message Passing Graph Neural Network 6

Transient Stability Evaluation of Independent Microgrid base...

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6th International Conference on Electronics Technology, ICET 2023

作者： Zhen, Jiubao Huang, Shufan Jia, xuwen du, Haocheng China Agricultural University College of Information and Electrical Engineering Beijing100083 China Shandong University Key Laboratory of Power System Intelligent Dispatch and Control of Ministry of Education Jinan250061 China

ISBN: (纸本)9798350337693

Virtual synchronous generator is used to control independent microgrid to provide inertia and damping support, but it often brings transient stability problems. due to the large number of nonlinear and non-smooth characteristics of highly electronic independent microgrid, it is difficult to analyze it by the traditional transient stability analysis method. In this paper, the independent microgrid controlled by virtual synchronization is taken as the object. Firstly, we compare the impact of detailed modeling of energy storage and simplified modeling on the transient stability, and then discuss the impact of current limiting link of virtual synchronous machine on the transient stability. Secondary, combined with the idea of graph neural network, we propose an independent microgrid transient stability evaluation model based on message passing graph neural network. The information corresponding to bus and transmission lines in microgrid is aggregated and updated by message passing mechanism, so as to depict the topological connection relationship of microgrid, and then consider the influence of topology structure on transient stability evaluation. Last, a WSCC-9 system with virtual synchronous machine is taken as an example. The results show that considering the energy storage detailed model and current limiting link can effectively improve the accuracy of stability analysis. The proposed method has stronger generalization ability and is more applicable to the microgrid system with variable topological structure. © 2023 IEEE.

关键词： Stability

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Conventional dendritic cells 2, the targeted antigen-presenting-cell, induces enhanced type 1 immune responses in mice immunized with CVC1302 in oil formulation

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IMMUNOLOGY LETTERS 2024年 267卷 106856-106856页

作者： du, Luping Lu, Haiyan Qiao, xuwen Zhang, Yuanpeng Hou, Liting Yu, Xiaoming Cheng, Haiwei Chen, Jin Zheng, Qisheng Hou, Jibo Tong, Guangzhi Jiangsu Acad Agr Sci Inst Vet Immunol & Engn Nanjing 210014 Jiangsu Peoples R China Jiangsu Acad Agr Sci Natl Res Ctr Engn & Technol Vet Biol Nanjing 210014 Jiangsu Peoples R China Minist Sci & Technol Nanjing Jiangsu Key Lab Food Qual & Safety State Key Lab Cultivat Base Nanjing 210014 Jiangsu Peoples R China Chinese Acad Agr Sci Shanghai Vet Res Inst Shanghai 200241 Peoples R China Nanjing Agr Univ Coll Vet Med Nanjing 210095 Jiangsu Peoples R China Jiangsu Acad Agr Sci 45 Zhongling StRoom A111 Nanjing Jiangsu Peoples R China

Multifunctional CD4+ T helper 1 (Th1) cells, producing IFN-gamma, TNF-alpha and IL-2, define a correlate of vaccinemediated protection against intracellular infection. In our previous study, we found that CVC1302 in oil formulation promoted the differentiation of IFN-gamma+/TNF-alpha+/IL-2+Th1 cells. In order to extend the application of CVC1302 in oil formulation, this study aimed to elucidate the mechanism of action in improving the Th1 immune response. Considering the signals required for the differentiation of CD4+ T cells to Th1 cells, we detected the distribution of innate immune cells and the model antigen OVA-FITC in lymph node (LN), as well as the quantity of cytokines produced by the innate immune cells. The results of these experiments show that, cDC2 and OVAFITC localized to interfollicular region (IFR) of the draining lymph nodes, inflammatory monocytes localized to both IFR and T cell zone, which mainly infiltrate from the blood. In this inflammatory niche within LN, CD4+ T cells were attracted into IFR by CXCL10, secreted by inflammatory monocytes, then activated by cDC2, secreting IL-12. Above all, CVC1302 in oil formulation, on the one hand, targeted antigen and inflammatory monocytes into the LN IFR in order to attract CD4+ T cells, on the other hand, targeted cDC2 to produce IL-12 in order to promote optimal Th1 differentiation. The new finding will provide a blueprint for application of immunopotentiators in optimal formulations.

关键词： CVC1302 Oil formulation Interfollicular region Inflammatory niche Th1 cells

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n-Type conjugated polymers comprising bithiophene imide and multifluorinated thiophene moieties synthesized by direct arylation polycondensation

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JOURNAL OF MATERIALS CHEMISTRY C 2022年第37期10卷 13905-13912页

作者： Cai, Houji Zhang, xuwen Shi, Yibo Xu, Chenhui Wang, Tianzuo Wang, Cheng du, Tian Deng, Yunfeng Geng, Yanhou Tianjin Univ Sch Mat Sci & Engn Tianjin 300072 Peoples R China Tianjin Univ Tianjin Key Lab Mol Optoelect Sci Tianjin 300072 Peoples R China Tianjin Univ Joint Sch Natl Univ Singapore & Tianjin Univ Int Campus Fuzhou 350207 Peoples R China

We synthesized four n-type conjugated polymers comprising a bithiophene imide (BTI) unit and 3,3 ',4,4 '-tetrafluoro-2,2 '-bithiophene (4FBT) or (E)-1,2-bis(3,4-difluorothien-2-yl)ethene (4FTVT) via direct arylation polycondensation, and comprehensively studied the optical, electrochemical and charge transport properties of the polymers. Increasing the BTI acceptor unit from one to two in the repeating unit slightly decreased the frontier molecular orbital levels of the polymers and blue-shifted their absorption spectra. Moreover, this change altered the molecular packing from an edge-on backbone orientation to bimodal packing with mixed edge-on and face-on orientations. When used as semiconductor layers in organic thin-film transistors, all four polymers exhibited unipolar n-type transport behavior with the highest saturation and a linear electron mobility of 0.72 and 0.67 cm(2) V-1 s(-1), respectively. Our findings suggest that direct arylation polycondensation can serve as an ecofriendly protocol for the synthesis of high-performance n-type conjugated polymers based on BTI through careful molecular design.

关键词： Ethylene

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Effect of grinding depth on the rotating bending fatigue properties of 40Cr steel

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FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES 2022年第4期45卷 1292-1295页

作者： Zhou, Honggen Chen, Jianzhi Bai, Xiaoxiang Li, Guochao Guan, Xiaoyan du, Qin Li, Ning Jing, xuwen Jiangsu Univ Sci & Technol Sch Mech Engn Zhenjiang 212003 Jiangsu Peoples R China Beijing North Vehicle Grp Co Ltd Beijing Peoples R China

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