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Chinese Journal of Aeronautics 2023年第2期36卷 388-401页

作者： xiaokang yue yuehong MA Ningsong QU Hansong LI College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Electrochemical milling is a modified technique of traditional electrochemical machining(ECM)that can be used to manufacture some helicopter transmission system *** use of rotary tools and an inner-jet electrolyte supply pattern can greatly improve the material removal rate(MRR)in a single ***,the feed speed is generally limited to minimize the tool *** increase the MRR,electrical discharge machining(EDM)is introduced into the electrochemical milling *** tool rotation is employed to interrupt the discharge and the high-conductivity salt solution and non-pulsed direct current power supply are also adopted to increase ECM,eventually,a new machining method is proposed,which can be called rotary sinking electrochemical discharge milling(RSECD milling).The mechanism of it is explored in this study by analyzing the machined current,MRR,surface morphology,and tool wear at different applied voltages and feed ***,the RSECD milling using the tool with a larger diameter is also conducted to further verify the *** particular,the MRR can be increased by 742.5%when using the tool with a diameter of 20 mm at the applied voltage of 20 V.

关键词： Electrochemical discharge machining Electrochemical milling High-conductivity salt solution Material removal rate Rotary tool

Comparison of electrochemical behaviors of Ti-5Al-2Sn-4Zr-4Mo-2Cr-1Fe and Ti-6Al-4V titanium alloys in NaNO_(3) solution

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International Journal of Minerals,Metallurgy and Materials 2024年第4期31卷 750-763页

作者： Jia Liu Shuanglu Duan xiaokang yue Ningsong Qu College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

The Ti-5Al-2Sn-4Zr-4Mo-2Cr-1Fe(β-CEZ)alloy is considered as a potential structural material in the aviation industry due to its outstanding strength and corrosion *** machining(ECM)is an efficient and low-cost technology for manufacturing theβ-CEZ *** ECM,the machining parameter selection and tool design are based on the electrochemical dissolution behavior of the *** this study,the electrochemical dissolution behaviors of theβ-CEZ and Ti-6Al-4V(TC4)alloys in NaNO3solution are *** open circuit potential(OCP),Tafel polarization,potentiodynamic polarization,electrochemical impedance spectroscopy(EIS),and current efficiency curves of theβ-CEZ and TC4 alloys are *** results show that,compared to the TC4 alloy,the passivation film structure is denser and the charge transfer resistance in the dissolution process is greater for theβ-CEZ ***,the dissolved surface morphology of the two titanium-based alloys under different current densities are *** low current densities,theβ-CEZ alloy surface comprises dissolution pits and dissolved products,while the TC4 alloy surface comprises a porous honeycomb *** high current densities,the surface waviness of both the alloys improves and the TC4 alloy surface is flatter and smoother than theβ-CEZ alloy ***,the electrochemical dissolution models ofβ-CEZ and TC4 alloys are proposed.

关键词： electrochemical machining dissolution behavior β-CEZ titanium alloy polarization curve current efficiency

Macro electrochemical milling and its hybrid variants

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Chinese Journal of Aeronautics 2024年第8期37卷 1-35页

作者： Ningsong QU Xiaolong FANG Junzhong ZHANG Huanghai KONG Yang LIU Minglu WANG xiaokang yue yuehong MA Zhihao SHEN Jiajie CHEN College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Mechanical Engineering Jiangsu UniversityZhenjiang 212003China School of Mechanical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Mechanical Engineering Hefei University of TechnologyHefei 230009China

Macro electromechanical milling has recently attracted increasing attention because numerous large thin-walled structures composed of difficult-to-cut materials are employed in the aerospace *** paper reviews recent developments in state-of-the-art macro electromechanical *** fundamental aspects of material removal mechanisms,such as the generation and breakdown behaviors of passive oxide films of typical difficult-to-cut materials,were *** methods for breaking down passive films are summarized,and simulation methods for the machining process coupling multiple physical fields are *** electrochemical milling methods,including fly mode electrochemical milling and sink electrochemical milling,are *** made to improve process performance,such as the material removal rate,surface quality,and machining accuracy,are *** addition,the main hybrid electrochemical milling methods,including electrochemical discharge milling,mechano-electrochemical milling,and electrochemical mill grinding,are also presented.

关键词： Electrochemical machining Electrochemical milling Material removal rate Surface quality Electrochemical discharge milling Electrochemical millgrinding

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土槿乙酸对白假丝酵母菌生物膜的抑制作用

中国微生态学杂志 2018年第3期30卷 279-282页

作者：郝小康李钰乐岳聪聪郭瑞林陕西中医药大学陕西咸阳712046 陕西中医药大学第二附属医院陕西咸阳712000

目的探讨土槿乙酸(pseudolaric acid B,PAB)对体外白假丝酵母菌生物膜的影响。方法甲基四氮盐(XTT)法检测不同浓度PAB和AMB(两性霉素B)对白假丝酵母菌生物膜的抑制作用。血清芽管试验检测不同浓度PAB对芽管生成的影响。结果 PAB对白假... 详细信息

目的探讨土槿乙酸(pseudolaric acid B,PAB)对体外白假丝酵母菌生物膜的影响。方法甲基四氮盐(XTT)法检测不同浓度PAB和AMB(两性霉素B)对白假丝酵母菌生物膜的抑制作用。血清芽管试验检测不同浓度PAB对芽管生成的影响。结果 PAB对白假丝酵母菌生物膜的SMIC50(抑制生物膜50%的药物浓度)为256~512μg/m L;1024和512μg/m L PAB对早期2 h生物膜的抑制率分别为(99.5±0.28)%和(97.1±0.38)%;512μg/m L PAB对早期(2 h)、中期(8 h)及成熟期(24 h)生物膜的抑制率分别为(97.1±0.38)%、(90.4±0.32)%和(80.1±0.67)%;不同浓度PAB的血清芽管试验显示,64μg/m L PAB可以完全抑制白假丝酵母菌的出芽生长,16μg/m L PAB可以抑制83.5%的白假丝酵母菌出芽生长。结论 PAB对体外白假丝酵母菌生物膜有抑制作用,对白假丝酵母菌的出芽生长过程抑制作用显著。

关键词：土槿乙酸白假丝酵母菌生物膜

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TC4复合材料电解钻孔加工技术研究

电加工与模具 2021年第2期 46-55,60页

作者：徐国梁李寒松岳小康马鑫李洁南京航空航天大学机电学院江苏南京210016

基于TC4复合材料研究了大余量去除和大直径孔的电解钻孔加工技术。首先,设计了工具阴极结构,在工具阴极侧面绝缘基础上采用电场仿真研究了工作圈高度对加工效果的影响,再针对不同钻孔深度进行流场仿真分析,揭示电解钻孔加工流场分布规... 详细信息

基于TC4复合材料研究了大余量去除和大直径孔的电解钻孔加工技术。首先,设计了工具阴极结构,在工具阴极侧面绝缘基础上采用电场仿真研究了工作圈高度对加工效果的影响,再针对不同钻孔深度进行流场仿真分析,揭示电解钻孔加工流场分布规律并探究了工具阴极端面出液孔数量对加工稳定性的影响;其次,对陶瓷绝缘和电泳绝缘两种不同绝缘方式下的工具耐用性进行了试验对比,结果表明:高电压下陶瓷绝缘层的耐用度明显优于电泳绝缘层;然后,采用陶瓷绝缘工具阴极对不同加工参数下的电解钻孔深度、入口直径、圆度、锥度等性能进行比较并优化了加工参数;最后,利用优选的参数加工得到入口直径21.43 mm、孔深39.19 mm、圆度误差0.028 mm和锥度0.068°的盲孔。

关键词：电解钻孔 TC4复合材料工作圈电场仿真流场仿真

电解铣磨加工GH4169电场仿真与试验研究

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机械制造与自动化 2020年第6期49卷 128-130,133页

作者：王系众李寒松付书星岳小康刘洋南京航空航天大学机电学院江苏南京210016

提出了一种带有锥形凹坑的电解铣磨加工GH4169磨轮。电场仿真与加工试验研究的结果表明:采用锥形凹坑磨轮,可使加工沟槽底面不同位置受到的腐蚀更加均匀,改善加工沟槽底面的平整性。

关键词：电解铣磨锥形凹坑 GH4169 平整性

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球头阴极电解铣磨加工TC4钛合金试验研究

机械制造与自动化 2021年第1期50卷 14-16页

作者：刘刚强李寒松牛屾岳小康王系众南京航空航天大学机电学院江苏南京210016

采用直径6 mm的球头阴极,通过内喷液式的供液方式,对TC4钛合金进行电解铣磨加工粗精加工试验研究。结果表明:采用球头阴极可以实现底面为曲面的沟槽加工,电解铣磨加工方法可以对沟槽进行连续的粗精加工,实现TC4钛合金曲面沟槽的高效精... 详细信息

采用直径6 mm的球头阴极,通过内喷液式的供液方式,对TC4钛合金进行电解铣磨加工粗精加工试验研究。结果表明:采用球头阴极可以实现底面为曲面的沟槽加工,电解铣磨加工方法可以对沟槽进行连续的粗精加工,实现TC4钛合金曲面沟槽的高效精密加工。

关键词：球头阴极电解铣磨 TC4 表面粗糙度

Mode decision for H.264 down-scaling video transcoding

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High Technology Letters 2006年第1期12卷 31-36页

作者：钱团结 Sun Jun Wang yue Chen Weian Yang xiaokang Institute of Image Communication and Information Processing Research Shanghai Jiaotong University Shanghai 200030 P.R. China

Although the coding modes of H.264 coded video would be changed by the transcoding process of spatial resolution reduction, there exists good correlation in prediction modes and prediction directions between input and output video. In this paper, we first introduce a new spatial resolution reduction transcoding architecture of intra coded frames where the distortion can be calculated directly in compression domain. We then propose a fast mode decision algorithm in which only a small part of rate distortion optimization （RDO） calculation is needed for mode decision. For 4×4 luma block, the proposed scheme has average 21.3% computation saving, compared to the cascaded pixel-domain transcoding scheme with the fast intra mode decision algorithm proposed in JVT-G013. For 16×16 luma block, RDO calculation is completely avoided in our scheme while the scheme in JVT-G013 needs 2 RDO calculations. Experimental results show that our scheme outperforms that of JVT-G013 in terms of significantly computasavings with negligible loss of PSNR

关键词： transcoding mode decision down-scaling H.264

Lattice Boltzmann Simulation of Nanoparticle Transport and Attachment in a Microchannel Heat Sink

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Fluid Dynamics & Materials Processing 2021年第2期17卷 301-317页

作者： xiaokang Tian Kai yue Yu You Yongjian Niu Xinxin Zhang School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing100083China Shunde Graduate School of University of Science and Technology Beijing Shunde528399China

The heat transfer performances of a microchannel heat sink in the presence of a nanofluid can be affected by the attachment of nanoparticle(NP)on the microchannel *** this study,the mechanisms underlying NP transport and attachment are comprehensively analyzed by means of a coupled double-distribution-function lattice Boltzmann model combined with lattice-gas *** this approach,the temperature distribution and the two-phase flow pattern are obtained for different values of the influential *** results indicate that the number of attached NPs decrease exponentially as their diameter and the fluid velocity *** increase in the wall temperature leads to an increase of the attached NPs,e.g.,the Al_(2)O_(3) NPs attached on the CuO microchannel wall increases by 105.8%in the range between 293 K and 343 *** are more attached NPs in microchannels with an irregular *** tendency of SiO2 NP to attach to the PDMS(polydimethylsiloxane),Fe and Cu walls is less significant than that for Al_(2)O_(3) and CuO NP;Moreover,NPs detach from the PDMS microchannel wall more easily than from the Cu and Fe microchannel *** SiO2 attachment layer has the greatest influence on the heat transfer performance although its thickness is thinner than that for Al_(2)O_(3) and CuO NPs under the same conditions.

关键词： Double-distribution-function lattice Boltzmann method lattice gas automata microchannel nanoparticle(NP) attachment

Deep learning-based large-scale named entity recognition for anatomical region of mammalian brain

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Quantitative Biology 2022年第3期10卷 253-263页

作者： xiaokang Chai Yachao Di Zhao Feng yue Guan Guoqing Zhang Anan Li Qingming Luo Britton Chance Center for Biomedical Photonics Wuhan National Laboratory for OptoelectronicsMoE Key Laboratory for Biomedical PhotonicsHuazhong University of Science and TechnologyWuhan 430074China Key Laboratory of Biomedical Engineering of Hainan Province School of Biomedical EngineeringHainan UniversityHaikou 570228China CAS Key Laboratory of Computational Biology Bio-Med Big Data CenterShanghai Institute of Nutrition and HealthUniversity of Chinese Academy of SciencesShanghai 200031China Research Unit of Multimodal Cross Scale Neural Signal Detection and Imaging Chinese Academy of Medical SciencesHUST-Suzhou Institute for BrainsmaticsJITRISuzhou 215123China CAS Center for Excellence in Brain Science and Intelligence Technology Chinese Academy of SciencesShanghai 200031China

Background:Images of anatomical regions and neuron type distribution,as well as their related literature are valuable assets for neuroscience *** are vital evidence and vehicles in discovering new phenomena and knowledge refinement through image and text big *** knowledge acquired from image data generally echoes with the literature accumulated over the *** knowledge within the literature can provide a comprehensive context for a deeper understanding of the image ***,it is quite a challenge to manually identify the related literature and summarize the neuroscience knowledge in the large-scale ***,neuroscientists are in dire need of an automated method to extract neuroscience knowledge from large-scale ***:A proposed deep learning model named BioBERT-CRF extracts brain region entities from the WhiteText *** model takes advantage of BioBERT and CRF to predict entity labels while ***:The proposed deep learning model demonstrated comparable performance against or even outperforms the previous models on the WhiteText *** BioBERT-CRF model has achieved the best average precision,recall,and F1 score of 81.3%,84.0%,and 82.6%,*** used the BioBERT-CRF model to predict brain region entities in a large-scale PubMed abstract dataset and used a rule-based method to normalize all brain region entities to three neuroscience ***:Our work shows that the BioBERT-CRF model can be well-suited for brain region entity *** rankings of different brain region entities by their appearance in the large-scale corpus indicate the anatomical regions that researchers are most concerned about.

关键词： brain region entity extraction literature mining WhiteText deep learning