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双针-板结构脉冲气泡放电等离子体固氮研究

原子与分子物理学报 2025年第6期42卷 122-128页

作者：赵少伟张丽方志南京工业大学电气工程与控制科学学院南京211816

大气压低温等离子体可以利用空气直接进行氧化固氮,具有反应条件温和、参数灵活可控、避免温室气体排放等优点.本文利用双针-板电极在水中形成气泡放电等离子体,以空气为放电气体进行了固氮研究,分析了产物浓度和固氮能耗的影响因素.研... 详细信息

大气压低温等离子体可以利用空气直接进行氧化固氮,具有反应条件温和、参数灵活可控、避免温室气体排放等优点.本文利用双针-板电极在水中形成气泡放电等离子体,以空气为放电气体进行了固氮研究,分析了产物浓度和固氮能耗的影响因素.研究结果表明,等离子体中含有丰富的氮原子、氧原子、氢原子、激发态氮分子等活性物种,可高效合成硝态含氮产物.研究发现,脉冲参数、电极间隙、工作气体组分对气泡放电等离子体的固氮性能有重要影响.装置最高NO~-_x合成速率为19.2μmol/min,最小能耗约为11 MJ/mol.此外还发现,电极间隙为6 mm时,固氮性能最优;空气中增加适量氧气(氧气/氮气比例为0.4)可以增强产物合成,降低能耗.

关键词：低温等离子体纳秒脉冲放电气液放电固氮

RF design optimization for the SHINE 3.9 GHz cavity

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Nuclear Science and Techniques 2020年第7期31卷 97-105页

作者： Yu-Xin zhang jin-fang Chen Dong Wang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201204China ShanghaiTech University Shanghai 201210China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China

The Shanghai high-repetition-rate XFEL and extreme light facility(SHINE)under construction is designed to be one of the most advanced free electron laser(FEL)facilities in the *** main part of the SHINE facility is an 8 GeV superconducting Linac operating in continuous wave(CW)*** Linac consists of seventy-five 1.3 GHz and two 3.9 GHz *** on the design and experience of 3.9 GHz cavities in the European X-ray free electron laser(E-XFEL)and the Linac coherent light source-II(LCLS-II)projects,we optimize the SHINE 3.9 GHz cavity design to adapt it for CW mode *** this paper,we present a particular redesign of the end group for the SHINE 3.9 GHz superconducting cavity that includes a redesign of the end cell and beam pipe to shift away the potentially troublesome lowest highorder modes(HOMs),a modification of the main coupler antenna,and a tuning of the HOM notch filter to meet the cavity *** losses calculations on the HOM coupler antennas show that the overheating on the inner conductor at the operating mode is diminished ***,we have also studied the HOMs to ensure there are no dangerously trapped modes in the optimized cavity design.

关键词： cavity antenna tuning

Design and analysis of a class of redundant collaborative manipulators with 2D large rotational angles

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Frontiers of Mechanical Engineering 2020年第1期15卷 66-80页

作者： Xiaodong jin Yuefa fang Dan zhang Xueling LUO Department of Mechanical Engineering Beijing Jiaotong UniversityBeijing 100044China Department of Mechanical Engineering Lassonde School of EngineeringYork UniversityToronto M3J 1P3Canada

The parallel spindle heads with high rotational capability are demanded in the area of multi-axis machine tools and 3D *** paper focuses on designing a class of 2R1T(R:Rotation;T:Translation)parallel spindle heads and the corresponding collaborative 5-axis manipulators with 2-dimension(2D)large rotational *** order to construct 2D rotational degrees of freedom(DOFs),a platform with 2D revolute joints is proposed *** on the constraint screw theory,the feasible limbs that can be connected in the platform are *** order to provide constant rotational axis for the platform,a class of redundant limbs are designed.A class of redundant 2R1T parallel spindle heads is obtained by connecting the redundant limbs with the platform and the redundant characteristics are verified by the modified Grübler-Kutzbach *** corresponding 5-axis collaborative manipulators are presented by constructing a 2-DOF series translational bottom moving *** inverse kinematics and the orientation workspace as well as the decoupling characteristics of this type of 2R1T parallel spindle heads are *** results show that these manipulators have large 2D rotational angles than the traditional A3/Z3 heads and can be potentially used in the application of multi-axis machine tools and the 3D printers.

关键词： parallel mechanism redundant mechanism large rotational angles machine tools 2R1T spindle head collaborative manipulator

Effects of adverse pressure gradient on Reynolds stresses inturbulent boundary layers

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航空动力学报 2017年第2期32卷 463-469页

作者： LUO Xiao-tian zhang Ce MA Wei TENG jin-fang School of Aeronautics and Astronautics Shanghai Jiao Tong University

The effects of adverse pressure gradient(APG)on Reynolds stresses in turbulent boundary layers(TBLs)with APG were *** difficulty of this work was attributable to the Reynolds stresses in TBLs with APG under two combined effects,i.e.:effect of upstream flow and effect of *** effect of upstream flow is an inherent effect no matter pressure gradient exists or *** individual effect was analyzed from absolute developments of Reynolds stresses in TBLs with zero pressure gradient(ZPG)*** of APG was then analyzed from absolute developments of Reynolds stresses in TBLs with *** showed that,for absolute development of mean streamwise Reynolds stresses,APG accelerated its development in TBL with ZPG;for absolute development of mean normal or shear Reynolds stresses,APG increased their magnitude in the outer part,and decreased their extent of large value region.

关键词： turbulent boundary layer adverse pressure gradient zero pressure gradient Reynolds stresses flat plate

Is procalcitonin to cortisol ratio really the right combination?

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World Journal of Emergency Medicine 2023年第2期14卷 171-172页

作者： Qi-fang Shi jin-song zhang Department of Emergency Medicine the First Affiliated Hospital of Nanjing Medical UniversityNanjing 210003China

Dear editor,We read with great interest the article by Liu H et al.[1]The authors proposed to explore the value of the procalcitonin-to-cortisol ratio(P/C ratio) in predicting the prognosis of patients with abdominal ... 详细信息

关键词： prognosis really

Adsorption of Zinc and Cyanide from Cyanide Effluents on Anionic Ion-exchange Resin

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Chemical Research in Chinese Universities 2013年第1期29卷 144-149页

作者： zhang Ya-li fang Tao YU Xian-jin School of Chemical Engineering Shandong University of Technology Zibo 255081 P. R. China

The adsorption of zinc and cyanide from cyanide effluents onto strong and weak basic anion exchange re sins was studied in a batch adsorption system. Factors influencing the adsorption rates such as resin selection, resin amounts, contact time and temperature were studied and scanning electron microscopyenergy disperse spectrosco py（SEMEDS） was used in the analysis. The present study shows that the adsorption capacity of resin 201 x7 is better than that of resin 301. The adsorption process was relatively fast and came to equilibrium after 60 min. The kinetic data were analyzed with three models and the pseudosecondorder kinetic model was found to agree with the expe rimental data well. The equilibrium data could also be described well by Langmuir isotherm model. Thermodynamic parameters such as enthalpy change（AH0）, free energy change（AG0） and entropy change（AS0） were calculated and the adsorption process was spontaneous and endothermic.

关键词： Ion-exchange Adsorption Adsorption isotherm Adsorption kinetics Thermodynamic parameter

Inhomogeneous Besov and Triebel-Lizorkin spaces associated with a para-accretive function and their applications

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Applied Mathematics(A Journal of Chinese Universities) 2023年第4期38卷 493-509页

作者： LIAO fang-hui LIU Zong-guang zhang Xiao-jin School of Mathematics and Computational Science Xiangtan UniversityXiangtan 411105China Department of Mathematics China University of Mining and TechnologyBeijing 100083China Department of basic curriculum North China Institute of Science and TechnologyLangfang 065201China

In this paper,using inhomogeneous Calderon’s reproducing formulas and the space of test functions associated with a para-accretive function,the inhomogeneous Besov and TriebelLizorkin spaces are *** applications,poin... 详细信息

关键词： para-accretive function Calderon's reproducing formula Besov space Triebel-Lizorkin space pointwise multiplier

Microstructures and mechanical properties of WE43 magnesium alloy prepared by friction stir processing

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Rare Metals 2020年第11期39卷 1267-1272页

作者： jin Li Da-Tong zhang fang Chai Wen zhang National Engineering Research Center of Near-Net-Shape Forming for Metallic Materials South China University of TechnologyGuangzhou510640China

Mg-3.99Y-3.81Nd-0.53 Zr(WE43)casting alloy was subjected to single-pass friction stir processing(FSP)at a constant processing speed of 60 mm-min^(-1)and various rotation speeds of 400,800,1200,and 1500 r·min^(-1),and microstructures and mechanical properties of the experimental materials were *** results in the generation of fine-grained microstructure,and fundamental breakage and dissolution of the coarse second *** the rotation speeds increasing,the average grain size of the FSP specimen in the stir zone first decreases and then increases,and the finest microstructure(~2μm)was prepared at the rotation speed of 800 r·min^(-1).Owing to the finer and more uniform microstructure,the mechanical properties of WE43 alloy after FSP are significantly *** variation tendency of the tensile properties is consistent with the change of the grain *** maximum tensile strength,elongation,and average microhardness of the FSP WE43 alloy obtained at 800 r·min^(-1)are 290 MPa,17.2%,and HV92.9,*** fracture morphology shows that small dimples can be observed on the FSP specimens,while the as-cast alloy fails through cleavage fracture.

关键词： WE43 magnesium alloy Friction stir processing Microstructure mechanical property Rare earth elements

A Real-Time Multi-Stage Architecture for Pose Estimation of Zebrafish Head with Convolutional Neural Networks

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Journal of Computer Science & Technology 2021年第2期36卷 434-444页

作者： zhang-jin Huang Xiang-Xiang He fang-Jun Wang Qing Shen School of Computer Science and Technology University of Science and Technology of ChinaHefei 230027China School of Data Science University of Science and Technology of ChinaHefei 230027China Anhui Province Key Laboratory of Software in Computing and Communication Hefei 230027China

In order to conduct optical neurophysiology experiments on a freely swimming zebrafish,it is essential to quantify the zebrafish head to determine exact lighting *** efficiently quantify a zebrafish head's behaviors with limited resources,we propose a real-time multi-stage architecture based on convolutional neural networks for pose estimation of the zebrafish head on *** stage is implemented with a small neural ***,a light-weight object detector named Micro-YOLO is used to detect a coarse region of the zebrafish head in the first *** the second stage,a tiny bounding box refinement network is devised to produce a high-quality bounding box around the zebrafish ***,a small pose estimation network named tiny-hourglass is designed to detect keypoints in the zebrafish *** experimental results show that using Micro-YOLO combined with RegressNet to predict the zebrafish head region is not only more accurate but also much faster than Faster R-CNN which is the representative of two-stage *** with DeepLabCut,a state-of-the-art method to estimate poses for user-defined body parts,our multi-stage architecture can achieve a higher accuracy,and runs 19x faster than it on CPUs.

关键词： convolutional neural network pose estimation real-time zebrafish