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代谢性炎症新概念及其与非酒精性脂肪性肝病发病机制和治疗靶点的联系

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实用医学杂志 2024年第18期40卷 2525-2529页

作者：牛春燕黄健康南京市溧水区人民医院消化内科南京211200 南京市溧水区人民医院神经内科南京211200

“代谢性炎症”由HOTAMISLIGIL于2006年提出,是一种由营养和能量过剩等代谢因素引起的慢性低度炎症,长期维持在亚急性水平。其中多种炎症细胞和免疫细胞浸润,多种炎症因子和免疫因子参与,炎症分子的表达或活性增强,引起炎症损伤。近年... 详细信息

“代谢性炎症”由HOTAMISLIGIL于2006年提出,是一种由营养和能量过剩等代谢因素引起的慢性低度炎症,长期维持在亚急性水平。其中多种炎症细胞和免疫细胞浸润,多种炎症因子和免疫因子参与,炎症分子的表达或活性增强,引起炎症损伤。近年对代谢相关脂肪性肝病的深入研究发现,代谢性炎症在NAFLD的发病机制中起到关键作用,其中涉及的相关炎症通路为靶向药物的研发提供了广阔前景。本文综述了代谢性炎症在NAFLD中的最新进展。

关键词：代谢性炎症非酒精性脂肪性肝病炎症分子炎症通路靶向药物

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GMAW潜弧焊电弧-熔池耦合行为数值分析

机械工程学报 2024年第2期60卷 159-167页

作者：樊丁李德全侯英杰黄健康冯毅兰州理工大学材料科学与工程学院兰州730050 兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室兰州730050

GMAW潜弧焊是GMAW在大电流范围内配合高速送丝实现高熔敷率、低飞溅率的一种高效焊接方法,可对中厚板进行有效焊接,显著提高焊接效率。为研究大电流细丝GMAW潜弧焊电弧-熔池耦合机理,建立了细丝GMAW潜弧焊电弧-熔池耦合数学模型,其中特... 详细信息

GMAW潜弧焊是GMAW在大电流范围内配合高速送丝实现高熔敷率、低飞溅率的一种高效焊接方法,可对中厚板进行有效焊接,显著提高焊接效率。为研究大电流细丝GMAW潜弧焊电弧-熔池耦合机理,建立了细丝GMAW潜弧焊电弧-熔池耦合数学模型,其中特别考虑了熔滴过渡和金属蒸气的影响。数值模拟结果表明:纯CO_(2)保护气下细丝GMAW潜弧焊电弧可稳定潜入熔池;GMAW潜弧焊电弧形态与普通GMAW钟罩形的电弧形态不同,电弧进入空腔后,在扩张的同时向下挖掘,使空腔深度显著增加;GMAW潜弧焊时,由热-力耦合引起的电弧-熔池动态演变是导致大熔深的根本原因,该模型的建立为GMAW潜弧焊的应用奠定了理论基础。

关键词： GMAW潜弧焊数值模拟电弧-熔池耦合行为

Three‑Dimensional Numerical Study on the Metal Rotating Spray Transfer Process of High‑Current GMAW

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Chinese Journal of Mechanical Engineering 2022年第6期35卷 234-246页

作者： Lei Xiao Ding Fan jiankang huang School of Materials Science and Engineering Lanzhou Jiaotong UniversityLanzhou 730070China State Key Laboratory of Advanced Processing and Recycling of Non‑ferrous Metals Lanzhou University of TechnologyLanzhou 730050China School of Materials Science and Engineering Lanzhou University of TechnologyLanzhou 730050China

A three-dimensional numerical model based on the volume-of-fluid(VOF)method is typically preferred for studying high-current gas metal arc welding(GMAW)metal transfer mechanism and then controlling *** is informed that the rotating spray transfer is extremely complicated,and some researchers have focused on simplified models without considering the energy conservation to make analysis manageable for the unstable metal transfer *** our created numerical model,the metal transfer of high-current GMAW with shielding gas of different conductivities has been studied by analyzing acting forces and fluid flows in the metal liquid column,especially for the contributions of the self-induced electromagnetic force,equivalent volume force of the capillary pressure of the surface tension(Named surface tension force in this work),static arc *** is found that the unbalanced electromagnetic force greatly promotes the metal rotating motion in 500 A metal inert gas(MIG)welding with pure argon shielding gas and it pushes the metal liquid column to *** the arc constricting effect in active shielding gas by simply changing the arc conductivity,it is found that the metal liquid column no longer rotates,it turns to swing since the unbalanced electromagnetic force is large enough to break the rotating *** calculated results of the metal liquid column deflected angle and rotating/swing frequency agree well with the experiment of high-speed camera observations.

关键词： Gas metal arc welding Rotating spray transfer Three-dimensional model Electromagnetic force Surface tension

Modeling, Simulation and Control of Pulsed DE-GMA Welding Process for Joining of Aluminum to Steel

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Chinese Journal of Mechanical Engineering 2014年第5期27卷 978-985页

作者： ZHANG Gang SHI Yu LI Jie huang jiankang FAN Ding State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of Technology

Joining of aluminum to steel has attracted significant attention from the welding research community,automotive and rail transportation *** current welding methods have been developed and applied,however,they can not precisely control the heat input to work-piece,they are high costs,low efficiency and consist lots of complex welding devices,and the generated intermetallic compound layer in weld bead interface is thicker.A novel pulsed double electrode gas metal arc welding（Pulsed DE-GMAW）method is *** achieve a stable welding process for joining of aluminum to steel,a mathematical model of coupled arc is established,and a new control scheme that uses the average feedback arc voltage of main loop to adjust the wire feed speed to control coupled arc length is proposed and ***,the impulse control simulation of coupled arc length,wire feed speed and wire extension is conducted to demonstrate the mathematical model and predict the stability of welding process by changing the distance of contact tip to work-piece（CTWD）.To prove the proposed PSO based PID control scheme’s feasibility,the rapid prototyping experimental system is setup and the bead-on-plate control experiments are conducted to join aluminum to *** impulse control simulation shows that the established model can accurately represent the variation of coupled arc length,wire feed speed and the average main arc voltage when the welding process is disturbed,and the developed controller has a faster response and adjustment,only runs about 0.1 *** captured electric signals show the main arc voltage gradually closes to the supposed arc voltage by adjusting the wire feed speed in 0.8 *** obtained typical current waveform demonstrates that the main current can be reduced by controlling the bypass current under maintaining a relative large total *** control experiment proves the accuracy of proposed model and feasibility of new control scheme *** beautiful and sm

关键词： pulsed double electrode gas metal arc welding dissimilar metals simulation and control particle swarm optimization

Self-Adaptive Control System for Additive Manufacturing Using Double Electrode Micro Plasma Arc Welding

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Chinese Journal of Mechanical Engineering 2021年第3期34卷 285-298页

作者： Nan Li Ding Fan jiankang huang Shurong Yu Wen Yuan Miaomiao Han School of Materials Science and Engineering Lanzhou University of TechnologyLanzhou 730050China State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals Lanzhou University of TechnologyLanzhou 730050China School of Mechanical and Electrical Engineering Lanzhou University of TechnologyLanzhou 730050China

Wire arc additive manufacturing(WAAM)has been investigated to deposit large-scale metal parts due to its high deposition efficiency and low material ***,in the process of automatically manufacturing the high-quality metal parts by WAAM,several problems about the heat build-up,the deposit-path optimization,and the stability of the process parameters need to be well *** overcome these issues,a new WAAM method based on the double electrode micro plasma arc welding(DE-MPAW)was *** circuit principles of different metal-transfer models in the DE-MPAW deposition process were analyzed *** effects between the parameters,wire feed rate and torch stand-off distance,in the process of WAAM were investigated *** addition,a real-time DE-MPAW control system was developed to optimize and stabilize the deposition process by self-adaptively changing the wire feed rate and torch stand-off ***,a series of tests were performed to evaluate the control system’s *** results show that the capability against interferences in the process of WAAM has been enhanced by this self-adaptive adjustment ***,the deposition paths about the metal part’s layer heights in WAAM are ***,the appearance of the WAAM-deposited metal layers is also improved with the use of the control system.

关键词： Double electrode microplasma arc welding Additive manufacturing Wire feed rate Torch stand-off distance Self-adaptive adjustment

Inconel 600镍基合金PAW+TIG接头微观组织及力学性能

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焊接学报 2024年第6期45卷 105-112页

作者：乔小丽曹帅武靖伟张建晓黄健康樊丁兰州兰石重型装备股份有限公司兰州730314 兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室兰州730050 中国科学院兰州化学物理研究所固体润滑国家重点实验室兰州730000

针对Inconel 600镍基合金在石化装备行业的应用焊接问题,选择合适的焊接工艺是其所面临的一项挑战.采用PAW+TIG工艺流程对厚度为6 mm的Inconel 600镍基合金进行焊接,应用光学显微镜、扫描电镜和拉伸试验机等对Inconel 600镍基合金PAW+TI... 详细信息

针对Inconel 600镍基合金在石化装备行业的应用焊接问题,选择合适的焊接工艺是其所面临的一项挑战.采用PAW+TIG工艺流程对厚度为6 mm的Inconel 600镍基合金进行焊接,应用光学显微镜、扫描电镜和拉伸试验机等对Inconel 600镍基合金PAW+TIG接头的微观组织及其性能进行研究.微观组织分析结果表明,接头焊缝表面成形光滑平齐,半椭圆状的鱼鳞纹均匀分布,接头母材区域和热影响区的组织均为细小的等轴晶奥氏体,其中热影响区晶粒的尺寸大于母材区,焊缝区域的组织为树枝晶;接头的抗拉强度达到589 MPa,接头断裂类型为韧性断裂,焊接接头具有良好的塑性和抗弯曲性能;焊缝处电化学腐蚀测试结果表明,在焊接热影响区域局部腐蚀敏感性增加,说明焊接接头的耐腐蚀性降低;对焊缝退火处理并进行性能测试的结果表明,退火后焊接接头析出针状第二相,其在晶界和孪晶界处形成了一定的强化效应,能够抑制晶粒长大并影响材料的整体性能.综合分析焊接接头微观组织及其性能表明,采用PAW+TIG的接头热稳定性较好,能够满足其在高温条件下的工作要求.

关键词：镍基合金 PAW+TIG 微观组织力学性能退火

Oscillation Modes of Weld Pool in Stationary GTA Welding Using Structure Laser Method

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Chinese Journal of Mechanical Engineering 2021年第5期34卷 243-258页

作者： Xingpei Wu jiankang huang Jing He Shien Liu Guangyin Liu Ding Fan School of Materials Science and Engineering Lanzhou University of TechnologyLanzhou 730050China Department of Mechanical Energy Engineering Southern University of Science and TechnologyShenzhen 518055China State Key Laboratory of Advanced Processing and Recycling of Non-Ferrous Metals Lanzhou University of TechnologyLanzhou 730050China

Researchers have recently attempted to monitor pool oscillations using the three-dimensional laser vision ***,the deficiency of simulation software will result in significant capital *** simulations and experiments are performed in this study,and the Bessel equation is used to analyze the oscillation mode of a weld *** laser dot matrix images of(0,1),(1,1),(2,1),and(0,2)oscillation modes at different times are obtained via structured laser optical measurement *** oscillation mode of a stationary gas tungsten arc weld pool is analyzed based on laser dot matrix images obtained from a structure laser *** show that the simulated laser dot matrix images are consistent with the experiment *** oscillation mode of the weld pool can be recognized based on the laser dot matrix *** study not only provides conditions for assessing the penetrating state of a weld pool,but also enable a further understanding of the oscillation mode of a weld pool and the development of more effective observation methods and measurement tools to effectively control and improve welding quality.

关键词： Weld pool surface GTA welding Bessel function Oscillation mode Geometric optics

Stress Distribution in the Cruciform Specimen under Transverse Tension Stress for SiC/Ti-6Al-4V Composites

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稀有金属材料与工程 2009年第A3期38卷 33-36页

作者： Yang Yanqing Yuan Meini Li jiankang huang Bin Luo Xian State Key Lab of Solidification Northwestern Polytechnical University Xi＇an 710072 China

The cruciform specimen was selected to obtain the transverse tensile behavior of SiC fiber reinforced titanium matrix composites. Moreover, the means of combining the unilaterally coupled finite element method with the transverse tensile test was developed to evaluate the interfacial normal bond strength of composites. The results showed that the initial non-linearity in the transverse stress-strain curve of SiC/Ti-6Al-4V occurs at the stress of 350 MPa. The means of combining the unilaterally coupled finite element method with the transverse tensile test is an effective method to predict the interfacial normal bond strength of composites. In addition, the interface failure mechanism of composites was analyzed in detail.

关键词：钛基复合材料物理性能应力有限元分析

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铜/钛异种金属激光焊接头组织及力学性能

焊接 2024年第7期 23-28,37页

作者：张杰徐建洲谢宇航张佳黄健康甘肃电器科学研究院甘肃天水741018 兰州理工大学有色金属先进加工与再利用国家重点实验室兰州730050

【目的】铜/钛异种金属焊接在航空航天、核工业等领域具有重要的潜在应用前景。该文旨在实现铜(T2)和钛(TA2)之间的连接。【方法】采用激光焊对铜/钛异种金属进行焊接工艺试验,分别对不同激光功率下接头宏观形貌、微观组织和力学性能进... 详细信息

【目的】铜/钛异种金属焊接在航空航天、核工业等领域具有重要的潜在应用前景。该文旨在实现铜(T2)和钛(TA2)之间的连接。【方法】采用激光焊对铜/钛异种金属进行焊接工艺试验,分别对不同激光功率下接头宏观形貌、微观组织和力学性能进行分析。【结果】结果表明,采用激光焊可以实现铜/钛接头的有效连接,接头呈现熔钎焊形式,由铜侧热影响区、熔合区和钛侧热影响区组成;当激光功率为1.8 kW时,接头的抗拉强度为127.2 MPa,约为铜母材的53%;显微硬度最小值处于铜侧,断裂发生在铜侧。随着激光功率的增加,熔钎焊界面形成Cu-Ti金属间化合物,厚度约为34μm,使其成为接头处的薄弱点。【结论】合理控制激光功率可有效抑制金属间化合物的生成,提高接头的力学性能。这些发现不仅为铜与钛的激光焊接提供了有价值的参考,也为进一步优化异种金属接头的设计和制造工艺提供了重要的试验依据。

关键词：钛铜激光焊显微组织力学性能