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Modeling and simulation of muzzle flow field of railgun with metal vapor and arc

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Defence Technology（防务技术） 2020年第4期16卷 802-810页

作者： Yuan Gao Yan-jie Ni Zhao-xin Wang ying-tao xu Yong Jin Bao-ming Li National Key Laboratory of Transient Physics Nanjing University of Science and TechnologyNanjing 210094JiangsuChina China Academy of Ordnance 100089BeijingChina

During the electromagnetic railgun launching process,there will be a complex flow field with high temperature in the muzzle area because of the high-speed friction,transition and seco ndary *** paper models the muzzle area of railgun when the projectile is far away from the muzzle,and the dynamic simulation of the flow field with secondary arc in the muzzle area is carried out based on the magneto hydrodynamic ***,a multi-component plasma transport model is used to analyze the muzzle arc plasma flow process of the mixed gas of Al vapor and the ***,the pressure boundary conditions are fitted by the dynamic mesh simulation *** current and voltage of the muzzle are obtained through the emission experiment of the railgun experimental *** load the current data into the simulation model and the voltage of experiments and simulations are compared,which proves the accuracy of the *** the plasma temperature and the composition of Al vapor in the muzzle flow process are analyzed in-depth.

关键词： Railgun Flow field Muzzle Plasma Simulation Al vapor

Effects of gonadotropin-releasing hormone antagonists on the expression of vascular endothelial growth factor and its receptors in a rat model of ovarian hyperstimulation syndrome

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Chinese Medical Journal 2008年第23期121卷 2434-2439页

作者： TONG Xiao-mei ZHANG Song-ying SONG tao xu Wei-hai LIN Xiao-na SHU Jing LIU Liu Department of Reproductive Medicine Sir Run Run Shaw Hospital Affiliated with School of Medicine Zhejiang University Hangzhou Zhejiang 310016 China

Background Ovarian hyperstimulation syndrome （OHSS） is one of the most life-threatening complications of assisted reproduction treatments. Gonadotropin-releasing hormone antagonists （GnRHanta） are thought to be effective in preventing this complication, and some clinical trials have found lower incidences of OHSS in patients treated with GnRHanta. Our aim was to investigate the effects of GnRHanta on vascular permeability and the expression of vascular endothelial growth factor （VEGF） and its receptors in a rat model of OHSS. Methods An immature early OHSS rat model was established. Three ovarian stimulation protocols were used： pregnant mare serum gonadotropin/human chorionic gonadotropin （hCG） alone, with a GnRHanta, or with a gonadotropin-releasing hormone agonists （GnRHa）. Blood and tissue samples were collected at 48 hours after hCG administration. Vascular permeability was evaluated by measuring the Evans-Blue content of extravasated peritoneal fluids. The expression of VEGF and its receptors, including fit-1 and KDR, were detected by reverse transcriptase-polymerase chain reaction and Western blotting. Results Treatment with both a GnRHanta and a GnRHa resulted in significant reductions in serum estradiol and peritoneal vascular permeability, as well as decreased ovarian expression of VEGF and its two receptors. However, GnRHanta treatment caused a greater reduction in serum estradiol concentrations, and in VEGF receptor mRNA expression than GnRHa. There were no significant reductions in the expression of VEGF or its receptors in extra-ovarian tissues, including the liver, lungs and peritoneum. Conclusion Our results reveal that GnRHanta are more potent than GnRHa in preventing early OHSS through down-regulation of the expression of VEGF and its receptors in hyperstimulated ovaries.

关键词： gonadotropin-releasing hormone antagonist gonadotropin-releasing hormone agonist ovarian hyperstimulation syndrome vascular endothelial growth factor

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以太网CFM的芯片级实现

光通信技术 2011年第1期35卷 31-34页

作者：胡建萍陶映旭杭州电子科技大学电子信息学院杭州310018

随着支持IEEE 802.1ag的芯片增多,交换机产品正迅速从连通错误管理的软件实现向硬件芯片实现过渡,从而使CCM帧发送速率提高到协议规定的最高300Hz。探讨了一种以硬件代替软件完成CFM功能的方案,重点详述了CFM功能中的连续性检测功能,详... 详细信息

随着支持IEEE 802.1ag的芯片增多,交换机产品正迅速从连通错误管理的软件实现向硬件芯片实现过渡,从而使CCM帧发送速率提高到协议规定的最高300Hz。探讨了一种以硬件代替软件完成CFM功能的方案,重点详述了CFM功能中的连续性检测功能,详细分析了采用硬件实现CCM帧发送与接收的方法,以及故障告警功能的实现。

关键词：以太网连通错误管理芯片硬件加速故障告警

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

混合溶剂中TS-1催化丙烯环氧化反应的研究

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燃料化学学报 2002年第3期30卷 262-266页

作者：程淑颖米镇涛徐大伟天津大学化工学院天津300072

对甲醇、异丙醇混合溶剂中的TS 1催化丙烯环氧化过程进行了实验研究。通过单因素实验和正交实验 ,系统考察了溶剂组成 (甲醇质量异丙醇质量 ) ,反应温度 ,H2 O2 浓度和TS 1催化剂浓度四个因素对反应的影响 ,得到了反应的最佳工艺条件... 详细信息

对甲醇、异丙醇混合溶剂中的TS 1催化丙烯环氧化过程进行了实验研究。通过单因素实验和正交实验 ,系统考察了溶剂组成 (甲醇质量异丙醇质量 ) ,反应温度 ,H2 O2 浓度和TS 1催化剂浓度四个因素对反应的影响 ,得到了反应的最佳工艺条件。在此条件下反应 30min ,H2 O2 转化率为 94 1% ,环氧丙烷选择性为 95 3% ,环氧丙烷收率为 89 7%。

关键词：混合溶剂丙烯环氧化反应 TS-1催化剂环氧丙烷过氧化氢溶剂效应甲醇异丙醇

ANALYSIS METHOD OF MIXED MODE CRACK IN 2D FINITE PIEZOELECTRIC MEDIA

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ANALYSIS METHOD OF MIXED MODE CRACK IN 2D FINITE PIEZOELECTR...

原位聚合制备PEDOT-PSS/PVA电磁波吸收功能复合导电织物

第三届全国压电和声波理论及器件技术研讨会

作者： Cui-ying FAN,Guang-tao xu,Ming-hao ZHAO Department of Engineering Mechanics,Zhengzhou University,Zhengzhou,Henan 450001,China.

In this paper,the Hybrid Extended Displacement Discontinuity-Charge Simulation Method(HEDD-CSM)[1]is used to study the mixed mode cracks in two-dimensional finite piezoelectric media under combined mechanical-electrical *** HEDD-CSM combines the extended displacement discontinuity method(EDDM) and the charge simulation method(CSM).The solution for an electrically impermeable crack is approximately expressed by a linear combination of fundamental solutions of the governing equations which includes the extended point force fundamental solutions with the sources placed at chosen points outside the domain of the problem under consideration and the extended Crouch fundamental solutions with the extended displacement discontinuities placed on the *** coefficients of the fundamental solutions are detennined by letting the approximated solution satisfy the conditions on the boundary of the domain and on the crack *** center cracks in piezoelectric strips are analyzed by HEDD-CSM. The stress intensity factors and the electric displacement intensity factor are *** the effect of finite domain size on these intensity factors is *** of the most interesting findings is that the intensity factor Kdecouples from K and K even in a finite piezoelectric medium.

关键词： Piezoelectric medium crack HEDD-CSM extended intensity factor extended displacement discontinuity method extended charge simulation method

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高分子学报 2017年第4期27卷 661-668页

作者：李昕许英涛郑一平张焱李从举陈光明北京服装学院材料科学与工程学院服装材料研究开发与评价北京市重点实验室北京100029 北京分子科学国家实验室中国科学院化学研究所北京100190

在自行织造的聚(3,4-乙烯二氧噻吩)-聚对苯乙烯磺酸钠/聚乙烯醇(PEDOT-PSS/PVA)导电织物表面,通过原位聚合法生成了致密的PEDOT-PSS导电聚合物覆盖层,所得织物称之为in situ PEDOT-PSS/PVA复合导电织物.研究发现,在优化的合成条件下,in ... 详细信息

在自行织造的聚(3,4-乙烯二氧噻吩)-聚对苯乙烯磺酸钠/聚乙烯醇(PEDOT-PSS/PVA)导电织物表面,通过原位聚合法生成了致密的PEDOT-PSS导电聚合物覆盖层,所得织物称之为in situ PEDOT-PSS/PVA复合导电织物.研究发现,在优化的合成条件下,in situ PEDOT-PSS/PVA复合导电织物具有优异的导电性能,其表面电阻最低可达2?/cm^2.电磁屏蔽性能测试结果表明,单层in situ PEDOT-PSS/PVA导电复合织物的电磁屏蔽效能可达12 dB左右,屏蔽率约为75%;在4~18 GHz的范围内,其电磁波反射率大部分都在-5^-10dB之间,可吸收75%~90%的电磁波,基本达到了军事吸波材料的要求.

关键词： PEDOT-PSS 复合导电织物原位聚合电磁波吸收功能

EZH2-dependent myelination following sciatic nerve injury

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Neural Regeneration Research 2025年第8期20卷 2382-2394页

作者： Hui Zhu Li Mu Xi xu Tianyi Huang ying Wang Siyuan xu Yiting Wang Wencong Wang Zhiping Wang Hongkui Wang Chengbin xue Research Center of Clinical Medicine Affiliated Hospital of Nantong UniversityKey Laboratory of Neuroregeneration of Jiangsu and Ministry of EducationCo-innovation Center of NeuroregenerationNMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology ProductsNantong UniversityNantongJiangsu ProvinceChina Medical School of Nantong University NantongJiangsu ProvinceChina Department of Neurology Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina Department of Rehabilitation Medicine Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina Department of Critical Care Medicine Nantong Fourth People’s HospitalNantongJiangsu ProvinceChina

Demyelination and remyelination have been major focal points in the study of peripheral nerve regeneration following peripheral nerve ***,the gene regulatory network of regenerated myelin differs from that of native *** of enhancer of zeste homolog 2(EZH2)hinders the differentiation,maturation,and myelination of Schwann cells in *** further determine the role of EZH2 in myelination and recovery post-peripheral nerve injury,conditional knockout mice lacking Ezh2 in Schwann cells(Ezh2^(fl/fl);Dhh-Cre and Ezh2^(fl/fl);Mpz-Cre)were *** results show that a significant proportion of axons in the sciatic nerve of Ezh2-depleted mice remain *** highlights the crucial role of Ezh2 in initiating Schwann cell ***,we observed that 21 days after inducing a sciatic nerve crush injury in these mice,most axons had remyelinated at the injury site in the control nerve,while Ezh2^(fl/fl);Mpz-Cre mice had significantly fewer remyelinated axons compared with their wild-type *** suggests that the absence of Ezh2 in Schwann cells impairs myelin formation and *** conclusion,EZH2 has emerged as a pivotal regulatory factor in the process of demyelination and myelin regeneration following peripheral nerve *** EZH2 activity during these processes may offer a promising therapeutic target for the treatment of peripheral nerve injuries.

关键词： demyelination EZH2 myelination peripheral nerve injury PRC2 remyelination Schwann cells sciatic nerve crush sciatic nerve transection

Observation of topological charge transformations in acoustic vortex using passive periodic systems

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 140-147页

作者： Di-Chao Chen Xie Liu Changqing xu Da-Jian Wu ying Cheng Xiao-Jun Liu School of Physics and Technology Nanjing Normal University Key Laboratory of Modern Acoustics School of Physics Nanjing University

Vortex transmutation utilizes a periodic system, which not only enables the alteration of the topological charge(TC) of unstable input vortices but also facilitates their transformation into stable structures. This approach is crucial for investigating the characteristics of vortices in various wave systems. Here, we achieve acoustic vortex TC transmutation by employing a welldesigned dual-structured plate external system(DPES). The interactions between the acoustic vortex and the finite-order discrete rotational symmetry lead to the transformation of its topological charge when complete rotational symmetry is broken to Nthorder discrete symmetry. Our results experimentally demonstrate the acoustic vortex TC transmutation based on passive artificial structures, enabling numerous applications in particle manipulation and information multiplexing as well as advancing our understanding and control over free-space acoustic vortices.

关键词： acoustic vortex topological charge transformation artificial structure