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基于驻留时间控制的压气机叶片前缘砂带磨削研究

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湖南大学学报（自然科学版） 2024年第4期51卷 1-9页

作者：黄云桂林秦涛王文玺邹莱李恒重庆大学机械与运载工程学院重庆400044 高端装备机械传动全国重点实验室重庆400044 中国航发南京轻型航空动力有限公司江苏南京211100

提出了一种面向叶片前缘廓形精准控制的机器人砂带磨削加工方法.以轴流压气机叶片为研究对象,结合半赫兹接触理论和有限元仿真获取了柔性磨具和叶片前缘的接触区域内的应力分布,基于Preston方程求解材料去除函数.遍历刀位点对控制点的... 详细信息

提出了一种面向叶片前缘廓形精准控制的机器人砂带磨削加工方法.以轴流压气机叶片为研究对象,结合半赫兹接触理论和有限元仿真获取了柔性磨具和叶片前缘的接触区域内的应力分布,基于Preston方程求解材料去除函数.遍历刀位点对控制点的磨削深度,建立全局材料去除矩阵,搭建驻留时间求解非线性方程组.采用带有阻尼因子的Tikhonov正则化消除大型稀疏病态矩阵对求解精度波动的影响,将所求驻留时间转换为对应刀位点的进给速度,生成机器人加工代码.磨削试验结果表明,基于驻留时间控制的机器人砂带磨削方法能够实现给定允差范围内叶片前缘廓形的精准加工,型面误差可以控制在0.02mm以内.

关键词：压气机砂带柔性磨削前缘廓形驻留时间

支气管镜下肺泡灌洗对支气管扩张伴感染患者炎症反应及血气分析的影响

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中国医疗器械信息 2024年第8期30卷 77-79页

作者：邹来武福建省南平市浦城县医院呼吸与危重症医学科福建南平353400

目的:探究支气管镜下肺泡灌洗对支气管扩张伴感染患者炎症反应及血气分析的影响。方法:选取2021年5月~2022年5月本院收治的60例支气管扩张伴感染患者为研究对象,按照随机数字表法分为两组。对照组(n=30)给予常规治疗,观察组(n=30)给予... 详细信息

目的:探究支气管镜下肺泡灌洗对支气管扩张伴感染患者炎症反应及血气分析的影响。方法:选取2021年5月~2022年5月本院收治的60例支气管扩张伴感染患者为研究对象,按照随机数字表法分为两组。对照组(n=30)给予常规治疗,观察组(n=30)给予支气管镜下肺泡灌洗治疗。连续治疗4周。对比两组患者的恢复情况、炎症反应相关指标以及并发症。结果:治疗4周后,观察组的肺部啰音改善时间、发烧改善时间、咳嗽改善时间、住院时间均短于对照组,有统计学差异(P0.05)。结论:支气管镜下肺泡灌洗治疗支气管扩张伴感染可有效缩短症状改善时间及住院时间,有助于提高支气管扩张伴感染患者肺功能,降低机体内炎症反应指标,且不增加并发症发生率,安全性相对较高。

关键词：支气管扩张感染炎症反应支气管镜下肺泡灌洗恢复情况并发症

A trajectory planning method on error compensation of residual height for aero-engine blades of robotic belt grinding

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Chinese Journal of Aeronautics 2022年第4期35卷 508-520页

作者： Chong LV lai zou Yun HUANG Xifan LIU Zhaorui LI Mingwang GONG Heng LI State Key Laboratory of Mechanical Transmission Chongqing UniversityChongqing 400044China

While the traditional trajectory planning methods are used in robotic belt grinding of blades with an uneven machining allowance distribution, it is hard to obtain the preferable profile accuracy and surface quality to meet the high-performance requirements of aero-engine. To solve this problem, a novel trajectory planning method is proposed in this paper by considering the developed interpolation algorithm and the machining allowance threshold. The residual height error obtained from grinding experiments of titanium alloy sample was compensated to modify the calculation model of row spacing, and a new geometric algorithm was presented to dynamically calculate the cutter contact points based on this revised calculation model and the dichotomy method. Subsequently, the off-line machining program is generated based on a double-vector controlling method to obtain an optimal contact posture. On this basis, three sets of robotic grinding tests of titanium alloy blades were conducted to investigate the advantages of the proposed *** comparative experimental results revealed that the presented algorithm had improved the surface profile accuracy of blade by 34.2% and 55.1%, respectively. Moreover, the average machined surface roughness was achieved to 0.3 μm and the machining efficiency was obviously promoted. It is concluded that this research work is beneficial to comprehensively improve the machined quality of blades in robotic belt grinding.

关键词： Aero-engine blade Double-vector controlling Interpolation algorithm Residual height error Robotic grinding

Pyogenic spondylitis caused by Escherichia coli: A case report and literature review

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World Journal of Clinical Cases 2023年第15期11卷 3583-3591页

作者： lai-Cheng zou Jin Qian Zhen-Yu Bian Xue-Peng Wang Tao Xie Department of Orthopedic Surgery The Fourth School of Clinical MedicineZhejiang Chinese Medical UniversityHangzhou 310053Zhejiang ProvinceChina Department of Orthopedic Surgery Affiliated Hangzhou First People’s HospitalZhejiang University School of MedicineHangzhou 310006Zhejiang ProvinceChina

BACKGROUND Pyogenic spondylitis is often manifested as atypical low back pain and fever,which makes it easy to be confused with other *** we report a case of pyogenic spondylitis and describe the diagnosis and treatment based on the related *** SUMMARY The reported case suffered from pyogenic spondylitis caused by Escherichia coli and complicated with bacteremia and psoas *** pyelonephritis was initially diagnosed due to atypical *** were improved from antibiotic treatment while developing progressive lower limb *** month post the admission,the patient underwent anterior lumbar debridement+autogenous iliac bone graft fusion+posterior percutaneous screw-rod internal fixation,and received 6 wk of antibiotic treatment after the *** 4 mo post the operation showed that the patient had no evident pain in the waist,and walked well with no evident dysfunction of lower *** Here we describe the application value of several imaging examinations,such as X-ray,computed tomography and magnetic resonance imaging,and certain tests like erythrocyte sedimentation rate and C-reactive protein in the clinical treatment of pyogenic *** disease requires early diagnosis and *** antibiotics should be used in early stages and surgical intervention should be taken if necessary,which may help for a speedy recovery and prevent the occurrence of severe complications.

关键词： Pyogenic spondylitis Escherichia coli Diagnosis and treatment Case report

Surface decoration of mesocarbon microbeads with multifunctional TiNbO_(4-x)@C coating layer as high rate and stable anode of Li-ion batteries

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Rare Metals 2024年第5期43卷 2053-2066页

作者： Jia-Mei lai Zhi-Min zou Yu Bai Yu-Tao Xing Chun-Hai Jiang Fujian Provincial Key Laboratory of Functional Materials and Applications Institute of Advanced Energy MaterialsSchool of Materials Science and EngineeringXiamen University of TechnologyXiamen 361024China Shanghai XFH Science and Technology Development Co. Ltd.Shanghai 200949China Fujian XFH New Energy Materials Co. Ltd.Yong'an 366000China Shenzhen XFH Science and Technology Co. Ltd.Shenzhen 518071China Laboratorio de Microscopia Eletronica de Alta Resolucao Centro de Caracterizagao Avangada Para a Industria de Petroleo(LaMAR/CAIPE)Universidade Federal FluminenseNiteroiRJ 24210-346Brazil

Surface modification of graphite anode with electroactive matters has been proven of a more practical strategy in enhancing the performance of Li-ion batteries than exploring alternative novel anode ***,rutile TiNbO_(4-x) nanoparticles with a tunnel structure are employed as multifunctional decoration substances in combination with a carbon coating layer to improve the rate and cycle properties of mesocarbon microbeads(MCMBs).As compared to pristine MCMB,the Li^(+)diffusion coefficients of the composite anodes are enhanced due to the synergistic effect of TiNbO_(4-x)@***,the overcharge and voltage polarization of the composite anodes at high rate are obviously minimized due to the current sharing effect of the high-potential TiNbO_(4-x).Moreover,the amorphous Li_(y)TiNbO_(4-x) converted from TiNbO_(4-x) in the initial lithiation process can deliver pseudocapacitive capacity to the composite anodes from the second *** of these functions of TiNbO_(4-x)@Ccoating layer have directly contributed to the improved rate and cycle performance of the MCMB/TiNbO_(4-x)@C composite *** one containing 12.0 wt%TiNbO_(4-x) exhibits a high reversible specific capacity of 118 m Ah·g^(-1)at 10C(1C=372 m A·g^(-1)),together with a high capacity retention of 90.9%after 300 cycles at 3C,which are all much superior to those of pristine MCMB.

关键词： Li-ion batteries MCMB TiNbO_(4-x)@C Surface decoration Rate capability

金刚石切削黑色金属时刀具磨损机理的摩擦磨损试验

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光学精密工程 2013年第7期21卷 1786-1794页

作者：周明邹莱哈尔滨工业大学机电工程学院黑龙江哈尔滨150001

为了降低黑色金属金刚石切削过程中的刀具磨损,提高表面加工质量和精度,对刀具磨损机理进行了研究。通过黑色金属金刚石摩擦磨损试验,模拟了实际切削过程中的刀具磨损行为;分别采用扫描电镜(SEM)、X射线能谱仪(EDS)以及拉曼光谱仪(RS)... 详细信息

为了降低黑色金属金刚石切削过程中的刀具磨损,提高表面加工质量和精度,对刀具磨损机理进行了研究。通过黑色金属金刚石摩擦磨损试验,模拟了实际切削过程中的刀具磨损行为;分别采用扫描电镜(SEM)、X射线能谱仪(EDS)以及拉曼光谱仪(RS)对工件表面形貌、实验前后工件表面化学组分变化以及金刚石磨损表面的晶体结构转变进行了检测,同时提出了用石墨化程度作为试验过程中评价金刚石磨损的指标。试验结果表明:金刚石的磨损主要与机械力和温度有关,摩擦速度和工件材料中的含碳量对其影响相对较小;石墨化磨损、扩散磨损和氧化磨损等磨损机理共存,其中石墨化为导致金刚石磨损的主要原因。结合红外热像仪测温和热传导理论推算,近似获得了摩擦界面的真实温度,且随着温度升高15%,金刚石石墨化程度显著加剧83%。作者提出,应当综合考虑热-力耦合作用下的刀具磨损机理,以便进一步探寻抑制刀具磨损的工艺措施。

关键词：超精密加工金刚石切削黑色金属摩擦磨损磨损机理

On Energy Assessment of Titanium Alloys Belt Grinding Involving Abrasive Wear Effects

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Chinese Journal of Mechanical Engineering 2023年第6期36卷 185-196页

作者： Mingcong Li Shudong Zhao Heng Li Yun Huang lai zou Wenxi Wang College of Mechanical and Vehicle Engineering Chongqing UniversityChongqing 400044China State Key Laboratory of Mechanical Transmissions Chongqing UniversityChongqing 400044China

Improved energy utilisation,precision,and quality are critical in the current trend of low-carbon green *** this study,three abrasive belts were prepared at various wear stages and characterised *** effects of abrasive belt wear on the specific grinding energy partition were investigated by evaluating robotic belt grinding of titanium plates.A specific grinding energy model based on subdivided tangential forces of cutting and sliding was developed for investigating specific energy and energy utilisation coefficient *** surface mor-phology and Abbott–Firestone curves of the belts were introduced to analyse the experimental findings from the per-spective of the micro cutting *** specific grinding energy increased with abrasive belt wear,especially when the belt was near the end of its ***,the belt wear could lead to a predominance change of sliding and chip formation *** highest EUC was observed in the middle of the belt life because of its retained sharp cutting edge and uniform distribution of the grit protrusion *** study provides guidance for balancing the energy consumption and energy utilization efficiency of belt grinding.

关键词： Belt grinding Wear Specific grinding energy Microtopography

机器人砂带磨削GH4169镍基高温合金表面完整性研究

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中国机械工程 2019年第17期30卷 2044-2050页

作者：段练黄云邹莱重庆大学机械传动国家重点实验室重庆400044 重庆市材料表面精密加工及成套装备工程技术研究中心重庆400021

采用机器人夹持GH4169镍基高温合金来进行砂带磨削试验。对试验装置进行了设计和分析,以确保砂带磨削过程中的磨削压力稳定;采用正交试验获得砂带磨削GH4169时的磨削深度;采用单因素试验确定砂带线速度和磨削压力对GH4169表面完整性的... 详细信息

采用机器人夹持GH4169镍基高温合金来进行砂带磨削试验。对试验装置进行了设计和分析,以确保砂带磨削过程中的磨削压力稳定;采用正交试验获得砂带磨削GH4169时的磨削深度;采用单因素试验确定砂带线速度和磨削压力对GH4169表面完整性的影响规律。试验结果表明:采用粒度为80号的陶瓷磨粒砂带加工GH4169时,其表面粗糙度在0.6~0.7μm范围内,且随着砂带线速度的增大而减小,随着磨削压力的增大而增大,表面硬度在430~485HV范围内,表面残余应力均为残余压应力,其值在-410^-60MPa范围内。

关键词： GH4169镍基高温合金砂带磨削磨削深度表面完整性

Study on internal quantum efficiency of blue InGaN multiple-quantum-well with an InGaN underneath layer

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Science China(Technological Sciences) 2010年第2期53卷 306-308页

作者： WANG JiaXing, WANG lai, ZHAO Wei, zou Xiang & LUO Yi National Laboratory for Information Science and Technology/State Key Laboratory on Integrated Optoelectronics, Department of Electronic Engineering, Tsinghua University, Beijing 100084, China 1. National Laboratory for Information Science and Technology/State Key Laboratory on Integrated Optoelectronics Department of Electronic Engineering Tsinghua University Beijing 100084 China

Blue InGaN multiple-quantum-well (MQW) samples with different InxGa1-xN (x=0.01–0.04) underneath layers (ULs) were grown by metal organic vapor phase epitaxy (MOVPE). Temperature dependent photoluminescence showed that the InGaN UL can improve the internal quantum efficiency (IQE) of MQW effectively due to strain release. And a maximum IQE of 50% was obtained when the thickness and In content of the InGaN UL were 60 nm and 0.01, respectively. Furthermore, the larger In content or thickness of the InGaN UL makes the IQE lower. Arrhenius fit to the experiment data showed that the IQE fall was mainly caused by the quantity increase of the nonradiative recombination centers, which was believed related to the accumulated stress in InGaN ULs.

关键词： InGaN underneath layer (UL) multiple-quantum-well (MQW) internal quantum efficiency (IQE) Arrhenius formula