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Influence of cutting and clamping forces on machining distortion of diesel engine connecting rod

INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY 2018年第1-4期99卷 897-910页

作者： Zhou, Honggen Wang, Chuhui Jing, xuwen Tian, Guizhong Li, Guochao liu, Shan Sun, Zhengkun Jiangsu Univ Sci & Technol Sch Mech Engn Zhenjiang Peoples R China Jiangsu Univ Sci & Technol Jiangsu Prov Key Lab Adv Mfg Marine Mech Equipmen Zhenjiang Peoples R China

As an important transmission component of diesel engines, the connecting rod has to meet a very high processing accuracy. However, as an elongated part, the connecting rod has a weak rigidity, and the unevenness of the cutting force and the clamping force during the machining processes will lead to the deformation of the connecting rod. In previous researches, cutting and clamping are always studied separately, and their interactions are neglected. In this paper, the finite element simulation method is used to analyze the deformation of the connecting rod. Based on the Deform-3D software, the article builds a connecting rod milling finite element simulation model and predicts the residual stress of the connecting rod milling simulation and the formation of milling chips. The residual stress of the simulation is compared with the residual stress of the experimental measurement and the simulation chip is compared with the actual chip to verify the accuracy of the simulation model, which provides a theoretical basis for the model construction of the next simulation study. Based on the Deform-3D software, simulation studies the influence of different milling parameters on the deformation of the connecting rods. And optimize the link milling process parameters. Based on ANSYS software, the effect of superposition of cutting force and clamping force on machining deformation of the connecting rod was simulated and analyzed. The resultant milling force should not be greater than 734N. This method makes up for the defects that cutting and clamping are studied separately and their interactions are neglected.

关键词： Connecting rod Machining deformation Finite element simulation Simulation model

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Medium-temperature furnace baking of 1.3 GHz 9-cell superconducting cavities at IHEP

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SUPERCONDUCTOR SCIENCE & TECHNOLOGY 2021年第9期34卷 095005-095005页

作者： He, Feisi Pan, Weimin Sha, Peng Zhai, Jiyuan Mi, Zhenghui Dai, xuwen Jin, Song Zhang, Zhanjun Dong, Chao liu, Baiqi Zhao, Hui Ge, Rui Zhao, Jianbing Mu, Zhihui Du, Lei Sun, Liangrui Zhang, Liang Yang, Conglai Zheng, Xiaobing Chinese Acad Sci Inst High Energy Phys Beijing 100049 Peoples R China Chinese Acad Sci Inst High Energy Phys Key Lab Particle Accelerat Phys & Technol Beijing 100049 Peoples R China Chinese Acad Sci Ctr Superconducting RF & Cryogen Inst High Energy Phys Beijing 100049 Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China

Recently, heat treatment in the range of 250 degrees C-500 degrees C has been attempted with the aim of improving the quality factor (Q) of superconducting radio-frequency (SRF) cavities worldwide. Herein, medium-temperature (mid-T) furnace baking experiments were conducted at the Institute of High Energy Physics to obtain higher Q values. First, 1.3 GHz 1-cell cavities received mid-T furnace baking at different temperatures, resulting in not only the improvement of Q but also an anti-Q-slope behavior. Furthermore, mid-T furnace baking was applied to six 1.3 GHz 9-cell cavities, all of which indicated higher Q and anti-Q-slope behavior. The average Q was 3.8 x 10(10) at 16 MV m(-1). The maximum gradients of the 9-cell cavities were 22.7-26.5 MV m(-1). Finally, the mid-T furnace baked 1.3 GHz 9-cell cavities were welded with helium vessel, with no degradation in the vertical tests. In addition, the mid-T furnace baking process was simplified in comparison with European X-ray Free Electron Laser and Linear Coherent Light Source because of the cancellation of light electro-polishing. This simplification is beneficial in the mass production of SRF cavities with high Q, which are widely adopted in free electron lasers and high-energy colliders.

关键词： superconducting cavity quality factor gradient medium-temperature furnace baking vertical test

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Occludin S490 Phosphorylation Regulates Vascular Endothelial Growth Factor-Induced Retinal Neovascularization

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AMERICAN JOURNAL OF PATHOLOGY 2016年第9期186卷 2486-2499页

作者： liu, xuwen Dreffs, Alyssa Diaz-Coranguez, Monica Runkle, E. Aaron Gardner, Thomas W. Chiodo, Vince A. Hauswirth, William W. Antonetti, David A. Univ Michigan Dept Ophthalmol & Visual Sci Kellogg Eye Ctr 1000 Wall St Ann Arbor MI 48105 USA Univ Penn Dept Pathol Perelman Sch Med Philadelphia PA 19104 USA Univ Florida Dept Ophthalmol Gainesville FL 32610 USA

Occludin is a transmembrane tight junction protein that contributes to diverse cellular functions, including control of barrier properties, cell migration, and proliferation. Vascular endothelial growth factor (VEGF) induces phosphorylation of occludin at S490, which is required for VEGF-induced endothelial permeability. Herein, we demonstrate that occludin S490 phosphorylation also regulates VEGF-induced retinal endothelial cell proliferation and neovascularization. Using a specific antibody, phospho-occludin was Located in centrosomes in endothelial cell cultures, animal models, and human surgical samples of retinal neovessels. Occludin S490 phosphorylation was found to increase with endothelial tube formation in vitro and in vivo during retinal neovascularization after induction of VEGF expression. More important, expression of occludin mutated at 5490 to Ala, completely inhibited angiogenesis in cell culture models and in vivo. Collectively, these data suggest a novel role for occludin in regulation of endothelial proliferation and angiogenesis in a phosphorylation-dependent manner. These findings may Lead to methods of regulating pathological neovascularization by specifically targeting endothelial cell proliferation.

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Thallium pollution in China and removal technologies for waters: A review

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ENVIRONMENT INTERNATIONAL 2019年 126卷 771-790页

作者： liu, Juan Luo, xuwen Sun, Yuqing Tsang, Daniel C. W. Qi, Jianying Zhang, Weilong Li, Nuo Yin, Meiling Wang, Jin Lippold, Holger Chen, Yongheng Sheng, Guodong Guangzhou Univ Guangdong Prov Key Lab Radionuclides Pollut Contr Key Lab Water Qual & Conservat Pearl River Delta Inst Environm Res Greater BayMinist EducSch Env Guangzhou 510006 Guangdong Peoples R China Hong Kong Polytech Univ Dept Civil & Environm Engn Hung Hom Kowloon Hong Kong Peoples R China Minist Environm Protect South China Inst Environm Sci Guangzhou 510655 Guangdong Peoples R China Helmholtz Zentrum Dresden Rossendorf Inst Ressourcenokol D-04318 Leipzig Germany Shaoxing Univ Coll Chem & Chem Engn Shaoxing 312000 Peoples R China

Thallium (Tl) is a typical toxic metal, which poses a great threat to human health through drinking water and the food chain (biomagnification). China has rich Tl-bearing mineral resources, which have been extensively explored and utilized, leading to release of large amounts of Tl into the environment. However, research on Tl pollution and removal techniques is relatively limited, because Tl has not been listed within the scope of environmental monitoring in China for several decades. This paper reviewed Tl pollution in wastewater arising from various industries in China, as well as the latest available methods for treating Tl-containing industrial wastewater, in order to give an outlook on effective technologies for controlling Tl pollution. Conventional physical and chemical treatment technologies are efficient at removing trace amounts of Tl, but it proved to be difficult to achieve the stringent environmental standard (<= 0.1-5 mu g/L) cost-effectively. Adsorption by using newly developed nanomaterials, and metal oxide modified polymer materials and microbial fuel cells are highly promising and expected to become next-generation technologies for remediation of Tl pollution. With the potential for greater Tl contamination in the environment under accelerated growth of industrialization, researches based on lab-scale implementation of such promising treatment technologies should be further expanded to pilot and industrial scale, ensuring environmental protection and the safety of drinking water for sustainable development. Comprehensive insights into experiences of Tl pollution in China and in-depth perspectives on new frontier technologies of Tl removal from wastewaters will also benefit other nations/regions worldwide, which are susceptible to high exposure to Tl likewise.

关键词： Thallium pollution Industrial wastewater treatment Anthropogenic source Nanomaterials

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基于模糊PID控制的船用胎架高度联控方法研究

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江苏科技大学学报（自然科学版） 2021年第1期35卷 58-65页

作者：刘金锋王镇景旭文唐明明曹旭武董建伟赵晨华江苏科技大学机械工程学院镇江212100 陕西柴油机重工有限公司兴平713100

胎架作为船舶分段建造变形控制的重要工装,但不具有联合调控与自适应控制能力,无法快速响应分段建造质量问题,为此本文提出基于模糊PID控制的船用胎架高度联控方法.首先,基于船舶分段拟合曲面建立胎架高度补偿模型,为胎架的自适应调控... 详细信息

胎架作为船舶分段建造变形控制的重要工装,但不具有联合调控与自适应控制能力,无法快速响应分段建造质量问题,为此本文提出基于模糊PID控制的船用胎架高度联控方法.首先,基于船舶分段拟合曲面建立胎架高度补偿模型,为胎架的自适应调控提供依据;其次,基于分段变形范围和受压载荷构建胎架间关联机制,达到胎架系统的动态联调;然后,利用模糊PID控制算法实现胎架高度的自适应调控,达到抑制分段外板变形的目的;最后,通过智能胎架系统对本方法进行验证分析,并与常规PID对比分析,表明本文方法具有较好的稳定性.

关键词：船舶分段建造智能胎架高度调控模糊PID

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大蒜提取物促进消化功能的研究

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西北药学杂志 2022年第6期37卷 37-43页

作者：毛旭文李琳琳史荣梅刘睿婷王莉飞李帅李新霞新疆医科大学药学院乌鲁木齐830011 新疆天然药物活性组分与释药技术重点实验室乌鲁木齐830011 新疆埃乐欣药业有限公司乌鲁木齐830011 新疆医科大学第二临床医学院乌鲁木齐830011

目的探讨大蒜提取物促进动物消化的作用。方法依据保健食品促进消化功能评价方法设计大鼠、小鼠实验,小鼠分为空白对照组、模型组、蒜氨酸组、大蒜辣素组和大蒜粉组。模型组和受试物组小鼠用盐酸洛哌丁胺诱导消化不良模型,灌胃不同质... 详细信息

目的探讨大蒜提取物促进动物消化的作用。方法依据保健食品促进消化功能评价方法设计大鼠、小鼠实验,小鼠分为空白对照组、模型组、蒜氨酸组、大蒜辣素组和大蒜粉组。模型组和受试物组小鼠用盐酸洛哌丁胺诱导消化不良模型,灌胃不同质量浓度的受试物30 d后,各组小鼠进行小肠运动实验,测定墨汁推进率、小鼠血清中肠神经递质乙酰胆碱、P物质、一氧化氮和血管活性肽含量。大鼠分为空白对照组、蒜氨酸组、大蒜辣素组和大蒜粉组,灌胃不同质量浓度的受试物30 d后,测定大鼠的体质量、体质量增质量、摄食量、食物利用率、1 h胃液量、胃蛋白酶活性、排出量、胃泌素、胃动力素和促胆囊收缩素含量。结果与模型组比,低、中、高剂量蒜氨酸及大蒜辣素以及大蒜粉组小肠墨汁推进率明显增高(P<0.01);低、中、高剂量蒜氨酸及大蒜辣素、大蒜粉组一氧化氮均显著下降(P<0.05);中、高剂量蒜氨酸及大蒜辣素组血管活性肽均显著下降(P<0.01);高剂量蒜氨酸、大蒜辣素组P物质均明显升高(P<0.05);低、中、高剂量蒜氨酸及大蒜辣素组乙酰胆碱明显升高(P<0.05),中、高剂量大蒜粉组乙酰胆碱明显升高(P<0.05)。与对照组比较,每周各组大鼠体质量、总增质量、总摄食量和总食物利用率差异无统计学意义。与对照组比较,高剂量蒜氨酸、大蒜辣素和大蒜粉组大鼠每小时排出的胃液量、胃蛋白酶活性、胃蛋白酶排出量、胃泌素、胃动力素和促胆囊收缩素显著增高(P<0.05)。结论蒜氨酸、大蒜辣素和大蒜粉具有促进动物消化的功能,具有一定的开发价值。

关键词：大蒜蒜氨酸促进消化功能

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计算机辅助个体化钉道设计在髋臼前柱和耻骨上支骨折螺钉经皮置入中的应用

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精准医学杂志 2022年第2期37卷 161-164页

作者：祝相如陈新张成栋刘巧聪刘国明李绪文王天瑞扈延龄青岛大学附属医院创伤外科山东青岛266100 青岛市城阳区人民医院急诊外科

目的探讨术前计算机辅助个体化钉道设计在髋臼前柱和耻骨上支骨折螺钉经皮置入术中的临床应用价值。方法回顾性分析我院2018年12月—2020年12月40例(共45侧)使用通道螺钉技术进行治疗的髋臼前柱或耻骨上支骨折患者。根据术前是否使用计... 详细信息

目的探讨术前计算机辅助个体化钉道设计在髋臼前柱和耻骨上支骨折螺钉经皮置入术中的临床应用价值。方法回顾性分析我院2018年12月—2020年12月40例(共45侧)使用通道螺钉技术进行治疗的髋臼前柱或耻骨上支骨折患者。根据术前是否使用计算机进行个体化钉道设计分为计算机辅助组(A组)和常规手法组(B组),A组患者术前均使用Mimics软件进行螺钉预置入,确定螺钉入钉点、螺钉方向和螺钉长度。B组按照手术操作者经验及以往解剖学研究得出的螺钉角度进行螺钉置入,不进行个体化设计。记录两组患者术中每枚螺钉的置入时间(置钉时间)、术中透视次数(透视次数)、螺钉长度、骨折愈合时间和术后6个月随访时的髋关节Merle D′Aubignéand Postel评分与骨盆Majeed功能评分。结果A组患者置钉成功率高于B组(χ^(2)=8.666,P<0.05),A组置钉时间、透视次数较B组明显减少(t=5.910、8.138,P<0.05),A组螺钉长度较B组明显缩短(t=18.863,P<0.05),两组患者骨折愈合时间及术后6个月时功能评分比较差异无显著性(P>0.05)。结论术前使用计算机对髋臼前柱和耻骨上支螺钉位置进行个体化设计,能够在保证手术效果的前提下缩短螺钉长度,从而降低拉力螺钉置入难度,能够为无或轻度移位的髋臼前柱和耻骨上支骨折的治疗提供新的方法,且临床疗效满意。

关键词：髋臼耻骨骨折,闭合性骨折固定术,内骨螺丝拉力螺钉计算机辅助设计

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Stress and optical constants in thin films of BaF₂-PrF₃: A potential Th-free infrared low-index evaporation material

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OPTIK 2018年 173卷 174-179页

作者： Lva, xuwen Zheng, Weimin Xie, Ping Li, Bin He, Weixiang Jing, Chao liu, Dingquan Shanghai Univ Dept Phys Shanghai 200444 Peoples R China Shandong Univ Sch Space Sci & Phys Weihai 264209 Peoples R China Chinese Acad Sci Shanghai Inst Tech Phys Shanghai 200083 Peoples R China Shanghai Tech Univ Sch Phys Sci & Technol Shanghai 200031 Peoples R China

Although PrF3 can be regarded as a potential infrared low-index evaporation material used in infrared antireflection to substitute for radioactive ThF4 because its thin films have a good transparency, the lower refractive index n and extinction coefficient k in the spectral range of thermal infrared, the greater tensile stress emerging in its layers will deteriorate the reliability and durability of antireflection coatings. In our investigation, BaF2-PrF3 thin films were deposited using electron beam evaporation from the sintered pellets of PrF3 admixed with BaF2. Stress in thin films was calculated from Stoney's equation on the basis of measuring the changes of radius of curvature of thin silicon strips. The stoichiometry of thin films was determined using the energy dispersive X-ray analysis (EDX). The optical constants of thin films were determined by fitting the measured spectral transmittance curves using Lorentz oscillators as a dispersion model. It can be observed that stress in BaF2-PrF3 thin films is obviously reduced with the increasing of the concentration of BaF2 in thin films and the sintered pellets. Moreover, it was also demonstrated that incorporation of BaF2 into PrF3 can reduce the refractive index of thin films, although BaF2-PrF3 thin films have a greater dispersion than that of PrF3 thin films. In addition, the lower value of extinction coefficient is also presented in thin films, like those of rare-earth fluorides.

关键词： Antireflection coatings Infrared Praseodymium fluoride Barium fluoride Electron beam evaporation Stress Optical constant

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High Q and high gradient performance of the first medium-temperature baking 1.3 GHz cryomodule

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Physical Review Accelerators and Beams 2024年第9期27卷 092003页

作者： Weimin Pan Jiyuan Zhai Feisi He Rui Ge Zhenghui Mi Peng Sha Song Jin Ruixiong Han Qunyao Wang Haiying Lin Guangwei Wang xuwen Dai Zhanjun Zhang Mei Li Minjing Sang Liangrui Sun Rui Ye Tongxian Zhao Shaopeng Li Keyu Zhu Baiqi liu Xiaolong Wang Xiangchen Yang Xiaojuan Bian Xiangzhen Zhang Huizhou Ma Jianbing Zhao Liang Zhang Hui Zhao Runbing Guo Zhihui Mu Conglai Yang Xiaobing Zheng Chao Dong Hongjuan Zheng Zhengze Chang Xiaochen Yang Tongming Huang Qiang Ma Zihan Wang Ming liu Wenzhong Zhou Senyu Chen Chinese Academy of Sciences Beijing 100049 China Beijing 100049 China

The world’s first 1.3 GHz cryomodule containing eight 9-cell superconducting radio-frequency (rf) cavities treated by medium-temperature furnace baking (mid-T bake) was developed at the Institute of High Energy Physics, Chinese Academy of Sciences. The 9-cell cavities in the cryomodule achieved an unprecedented high average intrinsic quality factor (Q0) of 3.8×1010 at 16 MV/m and 3.6×1010 at 21 MV/m in the horizontal test. The cryomodule can operate stably up to a total continuous wave rf voltage greater than 193 MV, with an average cavity usable accelerating gradient of more than 23 MV/m. The results significantly exceed the specifications of Circular Electron Positron Collider and Dalian advanced light source and the other high repetition rate free electron laser facilities [Linac Coherent Light Source II (LCLS-II), LCLS-II-high energy, Shanghai High Repetition Rate X-ray FEL and Extreme Light Facility, Shenzhen Superconducting Soft X-Ray Free Electron Laser, etc.]. There is evidence that the mid-T bake cavity may not require fast cooldown or long processing time in the cryomodule. This paper reviews the cryomodule performance and discusses some important issues in cryomodule assembly and testing.

关键词： Radio frequency techniques Superconducting RF

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Thallium isotopic fractionation in industrial process of pyrite smelting and environmental implications

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JOURNAL OF HAZARDOUS MATERIALS 2020年 384卷 121378-121378页

作者： liu, Juan Yin, Meiling Xiao, Tangfu Zhang, Chaosheng Tsang, Daniel C. W. Bao, Zhi'an Zhou, Yuting Chen, Yongheng Luo, xuwen Yuan, Wenhuan Wang, Jin Guangzhou Univ Sch Environm Sci & Engn Inst Environm Res Greater BayMinist Educ Key Lab Water Qual & Conservat Pearl River Delta Guangzhou 510006 Guangdong Peoples R China Hong Kong Polytech Univ Dept Civil & Environm Engn Hung Hom Kowloon Hong Kong Peoples R China Natl Univ Ireland Sch Geog & Archaeol & Ryan Inst Int Network Environm & Hlth Galway Ireland Northwest Univ Dept Geol State Key Lab Continental Dynam Xian 710069 Shaanxi Peoples R China

Thallium (Tl) is typical rare element with severe toxicity comparable to Hg and Pb. To track Tl pollution, isotopic fractionation of Tl was evaluated during pyrite smelting for sulfuric acid production. Large variations in Tl isotope compositions were observed among the pyrite ore (PO) and its four different smelting wastes. The starting raw PO had an epsilon Tl-205 value of + 1.28. The fluidized-bed furnace slag generated by high-temperature smelting had the heaviest epsilon Tl-205 (+ 16.24) in the system. Meanwhile, the boiler fly ash (epsilon Tl-205 = +8.34), cyclone fly ash (epsilon Tl-205 = + 2.17), and electrostatic precipitation fly ash (epsilon Tl-205 = -1.10), with decreasing grain sizes during the treatment processes, were characterized by elevated levels of Tl contents and substantial enrichment in the light Tl isotopes relative to the furnace slag. Further calculation and high-resolution transmission electron microscopy indicated that Tl isotope fractionation could be governed by both Rayleigh-type fractionation and adsorption of volatilized Tl by particles of various grain sizes. According to the substantial differences in the PO from its smelting wastes and the measurement precision of isotopic fractionation, it is suggested that Tl isotopes can serve as a new tool for tracing pollution of Tl.

关键词： Potentially toxic elements Fly ash Source apportionment Isotopic signature Pyrite smelting

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