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基于蜗杆砂轮磨削斜齿面原理性自然扭曲计算及三截面参数修形优化试验验证研究

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现代制造工程 2024年第1期 74-79页

作者：王泽贵郭丽芳上海电子信息职业技术学院机械与能源工程学院高端装备机械可靠性与智能诊断研究中心上海201411 上海汽车变速器有限公司技术中心上海201807

基于蜗杆砂轮磨削斜齿轮齿面原理性自然扭曲问题,计算推导磨齿加工接触迹方程,选取齿形齿向评价范围,建立齿面扭曲模型,求得蜗杆砂轮磨削斜齿轮自然扭曲下的齿形齿向角度偏差值,优化与自然扭曲相关的齿轮微观修形参数,包括减小齿向鼓形... 详细信息

基于蜗杆砂轮磨削斜齿轮齿面原理性自然扭曲问题,计算推导磨齿加工接触迹方程,选取齿形齿向评价范围,建立齿面扭曲模型,求得蜗杆砂轮磨削斜齿轮自然扭曲下的齿形齿向角度偏差值,优化与自然扭曲相关的齿轮微观修形参数,包括减小齿向鼓形量、调整配对齿轮鼓形量、调整配对齿轮扭曲量,经试验验证可有效降低或补偿蜗杆砂轮磨削斜齿轮自然扭曲,即可有效改善齿轮承载性能,减小齿轮啮合冲击,提升传动精度和振动噪声水平。

关键词：齿面扭曲微观修形磨齿斜齿轮

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姿控推力室隔热框断裂故障分析及改进

载人航天 2024年第3期30卷 372-376页

作者：曹晶熊莉芳王茜西安航天动力研究所西安710100

针对某姿控动力系统推力室在力学环境试验过程中发生的隔热框断裂故障,对故障部位进行断口分析和结构强度分析,发现在高量级随机振动条件下隔热框支撑肋根部存在严重的应力集中,导致发生疲劳断裂。通过改进隔热框支撑肋结构,经强度分析... 详细信息

针对某姿控动力系统推力室在力学环境试验过程中发生的隔热框断裂故障,对故障部位进行断口分析和结构强度分析,发现在高量级随机振动条件下隔热框支撑肋根部存在严重的应力集中,导致发生疲劳断裂。通过改进隔热框支撑肋结构,经强度分析和推力室力学环境试验验证,隔热框未再发生类似故障,表明改进措施方案可靠有效。

关键词：推力室力学试验疲劳断裂故障分析

P-Rex1 Overexpression Results in Aberrant Neuronal Polarity and Psychosis-Related Behaviors

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Neuroscience Bulletin 2019年第6期35卷 1011-1023页

作者： Qiongwei Li lifang wang Yuanlin Ma Weihua Yue Dai Zhang Jun Li Peking University Institute of Mental Health Peking University Sixth HospitalBeijing 100191China National Health Center Key Laboratory of Mental Health(Peking University) Beijing 100191China National Clinical Research Center for Mental Disorders Peking University Sixth HospitalBeijing 100191China Peking-Tsinghua Center for Life Sciences Peking UniversityBeijing 100871China PKU-IDG/McGovem Institute for Brain Research Peking UniversityBeijing 100871China

Neuronal polarity is involved in multiple developmental stages, including cortical neuron migration,multipolar-to-bipolar transition, axon initiation, apical/basal dendrite differentiation, and spine formation. All of these processes are associated with the cytoskeleton and are regulated by precise timing and by controlling gene expression. The P-Rex1(phosphatidylinositol-3,4,5-trisphosphate dependent Rac exchange factor 1) gene for example, is known to be important for cytoskeletal reorganization, cell motility, and migration. Deficiency of P-Rex1 protein leads to abnormal neuronal migration and synaptic plasticity, as well as autism-related behaviors.Nonetheless, the effects of P-Rex1 overexpression on neuronal development and higher brain functions remain unclear. In the present study, we explored the effect of P-Rex1 overexpression on cerebral development and psychosis-related behaviors in mice. In utero electroporation at embryonic day 14.5 was used to assess the influence of P-Rex1 overexpression on cell polarity and migration.Primary neuron culture was used to explore the effects of P-Rex1 overexpression on neuritogenesis and spine morphology. In addition, P-Rex1 overexpression in the medial prefrontal cortex(m PFC) of mice was used to assess psychosis-related behaviors. We found that P-Rex1 overexpression led to aberrant polarity and inhibited the multipolar-to-bipolar transition, leading to abnormal neuronal migration. In addition, P-Rex1 overexpression affected the early development of neurons, manifested as abnormal neurite initiation with cytoskeleton change,reduced the axon length and dendritic complexity, and caused excessive lamellipodia in primary neuronal culture.Moreover, P-Rex1 overexpression decreased the density of spines with increased height, width, and head area in vitro and in vivo. Behavioral tests showed that P-Rex1 overexpression in the mouse m PFC caused anxiety-like behaviors and a sensorimotor gating deficit. The appropriate P-Rex1 level plays a critical role in the developing cereb

关键词： P-Rex1 Neurodevelopment Polarity Lamellipodia Psychosis-related behavior

Energetics and structures of hydrogen-vacancy clusters in tungsten based on genetic algorithm

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Science China(Physics,Mechanics & Astronomy) 2018年第10期61卷 100-103页

作者： lifang wang XiaoLin Shu GuangHong Lu Fei Gao Department of Physics Beihang University Department of Nuclear Engineering and Radiological Sciences University of Michigan

The behavior of hydrogen(H)in metals has been a longstanding research topic in materials science.One of the most compelling subjects is the deleterious effects of H on the microstructural evolution of materials;these effects include H embrittlement,superabundant vacancy formation,and blistering.Vacancies have been demonstrated through both experiments and computational simulations to have strong H trapping effects[1],resulting in increased H retention[2],

关键词：微结构基因算法聚类氢材料科学计算模拟表面修正钨

融合卷积和Transformer的多尺度肝肿瘤分割方法

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计算机工程与应用 2024年第4期60卷 270-279页

作者：陈丽芳罗世勇江南大学人工智能与计算机学院江苏无锡214122

精确的肝脏和肝脏肿瘤自动分割方法对帮助医生进行肝癌诊断、治疗和术后观察具有重要的意义。由于卷积的局部性,现有基于卷积的方法难以建立长距离的依赖关系。Transformer的级联注意力机制可以建立全局的信息关联,但是会破坏局部细节... 详细信息

精确的肝脏和肝脏肿瘤自动分割方法对帮助医生进行肝癌诊断、治疗和术后观察具有重要的意义。由于卷积的局部性,现有基于卷积的方法难以建立长距离的依赖关系。Transformer的级联注意力机制可以建立全局的信息关联,但是会破坏局部细节。基于此,提出了一种融合卷积和Transformer的特征建模方法。该方法通过混合嵌入的方式交互融合局部表示和全局表示,最大程度地建立不同分辨率下的全局依赖关系。在跳跃连接处通过多级特征融合模块捕捉来自不同编码阶段的上下文信息以获取更丰富的语义信息。为了应对肝脏肿瘤在大小和形状上的变化,使用可变形多尺度模块提取肿瘤的多尺度特征。实验主要采用Dice相关性系数(Dice similarity coefficient,DSC)作为评价指标,在LiTS17数据集上肝脏和肿瘤的DSC分别为0.920和0.748,结果表明提出的网络相比基线具有更准确的肝脏肿瘤分割结果。

关键词：医学图像肿瘤分割 Transformer 卷积神经网络多尺度特征融合

大学英语新形态教材:内涵、开发原则与核心特征

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外语界 2024年第1期 57-64页

作者：杨莉芳北京外国语大学英语学院北京100089

建设深度融合信息技术、适应互联网时代学习需求的大学英语新形态教材是教育数字化战略发展的现实要求。本文通过提炼大学英语新形态教材的本质属性界定其内涵,然后阐述大学英语新形态教材开发的基本原则,并在此基础上分析大学英语新形... 详细信息

建设深度融合信息技术、适应互联网时代学习需求的大学英语新形态教材是教育数字化战略发展的现实要求。本文通过提炼大学英语新形态教材的本质属性界定其内涵,然后阐述大学英语新形态教材开发的基本原则,并在此基础上分析大学英语新形态教材的核心特征,期望能为大学英语新形态教材的开发、研究与评价提供参考。

关键词：新形态教材大学英语教学内涵开发原则核心特征

Advances in Research of Anti-tumor Effect of Aconiti Radix

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Medicinal Plant 2024年第2期15卷 80-83页

作者： Jing GAO Fanbo JING lifang FENG Wen XU Changkai ZHOU The Third People s Hospital of Qingdao Qingdao 266041China The Affiliated Hospital of Qingdao University Qingdao 266100China

In this paper,the anti-tumor effects of Aconiti Radix were reviewed and summarized,and the clinical feasibility of Aconiti Radix as a potential anti-tumor drug was analyzed,in order to provide a useful reference for t... 详细信息

关键词： Aconiti Radix Anti-tumor Research advances Feasibility analysis

激光内送粉变姿态熔覆非水平熔池流场的数值模拟

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表面技术 2024年第9期53卷 190-199,208页

作者：陈海俊朱刚贤贺继宏王丽芳苏州大学机电工程学院江苏苏州215137 苏州大学工程训练中心江苏苏州215137

目的提高激光内送粉变姿态熔覆层成形质量,对变姿态熔覆时非水平熔池流场随基板倾斜角的演变规律进行研究。方法首先,利用FLUENT软件中离散相模型对喷嘴流场进行模拟,获取粉末频次的分布规律。其次,采用流体体积法耦合熔化/凝固模型对... 详细信息

目的提高激光内送粉变姿态熔覆层成形质量,对变姿态熔覆时非水平熔池流场随基板倾斜角的演变规律进行研究。方法首先,利用FLUENT软件中离散相模型对喷嘴流场进行模拟,获取粉末频次的分布规律。其次,采用流体体积法耦合熔化/凝固模型对熔池流场进行计算。通过施加质量源项引入同步送粉,施加能量源项模拟激光热输入,选取姿态角为30°、60°、90°进行计算,对熔池流场及熔覆层界面进行追踪分析。最后,基于激光内送粉熔覆工艺进行实验测定。结果粉斑内粉末量呈“中间均匀,两端密集”的分布规律。熔池流动为“双环流”分布特征,但流动方向受重力影响,产生偏转。取3种姿态角计算时间同为0.3 s时,熔池中心处流体的偏转角分别为2°、4°、6°,并且随着倾斜角的增大,熔覆层高度分别增加了0.28%、0.83%、1.45%,熔覆层宽度减小了1.19%、1.28%、1.73%,熔覆层顶点偏移量增大到48.08、86.54、105.76μm。最后结合实验测定,数值计算与实验结果一致。结论Marangoni应力使得激光内送粉熔覆熔池流体产生由中心向边界流动的“双环流”分布特征,非水平熔池流动方向受重力影响产生偏转。随着基板倾斜角增大,熔覆层截面高度增加、宽度降低、顶点偏移量增加。为提高不便摆平非水平基面的激光内送粉变姿态熔覆再制造成形质量提供了指导。

关键词：激光熔覆光内送粉变姿态熔池流场数值模拟

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Freezing-directed construction of enzyme/nano interfaces:Reagentless conjugation,superior activity,and better stability

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Chinese Chemical Letters 2024年第1期35卷 471-474页

作者： Ke Quan Jiajie Tong lifang Chen Shuyao Fang Mengjiao Li Linlin Wu Zhihe Qing Hunan Provincial Key Laboratory of Cytochemistry School of Food and BioengineeringSchool of Chemistry and Chemical EngineeringChangsha University of Science and TechnologyChangsha 410114China Department of Oncology Tengzhou Central People’s Hospital Affiliated Xuzhou Medical UniversityTengzhou 277500China

Immobilizing enzyme to nano interfaces has demonstrated to be a favorable strategy for prompting the industrialized application of enzyme.Despite tremendous endeavor has been devoted to using gold nanoparticles(AuNPs)as conjugation matrix due to its fascinating physico-chemical properties,maintaining enzymatic activity while circumventing cumbersome modification remains a formidable challenge.Herein,the freezing-directed conjugation of enzyme/nano interfaces was constructed without extra reagent.As the proof of concept,glucose oxidase(GOx)was chosen as model enzyme.The one-pot conjugation process can be facilely completed at−20°C under aqueous solution.Moreover,with the loading of GOx on AuNP at freezing,the enzyme exhibited superior catalytic activity and stability upon thermal and pH perturbation.The mechanism of boosted activity was then discussed in detail.It was found that higher loading density under freezing condition and more enzyme tending to bind AuNPs via Au-S bond were the main factors for the superior activity.More importantly,this methodology was universal and can also be applied to other enzyme which contains natural cysteine,such as horseradish peroxidase(HRP)and papain.This facile conjugation strategy accompanied by remarkable bioactivity expand the possibilities for enzymatic biosensing,microdevice and even drug delivery.

关键词： Enzyme conjugation Freezing AuNPs Catalytic activity