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Laser Spot Center Detection and Comparison Test
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作者 Jun ZHU Zhengjie XU +1 位作者 Deli FU Cong HU 《光子传感器:英文版》 EI CAS CSCD 2019年第1期49-52,共4页
High efficiency and precision of the pot center detection are the foundations of avionics instrument navigation and optics measurement basis for many applications.It has noticeable impact on overall system performance... High efficiency and precision of the pot center detection are the foundations of avionics instrument navigation and optics measurement basis for many applications.It has noticeable impact on overall system performance.Among them,laser spot detection is very important in the optical measurement technology.In order to improve the low accuracy of the spot center position,the algorithm is improved on the basis of the circle fitting.The pretreatment is used by circle fitting,and the improved adaptive denoising filter for TV repair technology can effectively improves the accuracy of the spot center position.At the same time,the pretreatment and de-noising can effectively reduce the influence of Gaussian white noise,which enhances the anti-jamming capability. 展开更多
关键词 SPOT TV REPAIR TECHNOLOGY SPOT CENTER
肺泡灌洗液效应T细胞检测对涂阴肺结核的快速诊断价值 预览
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作者 王琳 施军卫 +4 位作者 陈俊林 陈晓丽 秦志华 郑宏 唐建美 《临床肺科杂志》 2019年第4期588-591,共4页
目的探讨检测患者肺泡灌洗液(bronchoalveolar lavage fluid,BALF)中的效应T细胞对涂阴肺结核快速诊断价值。方法收集2016-2017年在南通市第六人民医院结核科住院的120例疑似肺结核患者的BALF,经确诊后分为涂阳肺结核组43例、涂阴肺结核... 目的探讨检测患者肺泡灌洗液(bronchoalveolar lavage fluid,BALF)中的效应T细胞对涂阴肺结核快速诊断价值。方法收集2016-2017年在南通市第六人民医院结核科住院的120例疑似肺结核患者的BALF,经确诊后分为涂阳肺结核组43例、涂阴肺结核组56例,非结核感染组21例。利用结核感染效应T细胞斑点试验(T-SPOT)对所有患者的BALF中的效应T细胞进行检测,评估其阳性率;收集涂阴组患者BALF其他结核检测指标:结核分枝杆菌RNA恒温扩增实时荧光检测技术(SAT-TB)、使用BACTEC MGIT960系统的结核分枝杆菌快速培养(960培养)、利福平耐药实时荧光定量核酸扩增检测技术(Xpert MTB/RIF)及外周血T-SPOT检测,与BALF T-SPOT进行对比,并计算BALF T-SPOT对于涂阴肺结核的诊断价值。结果涂阳组和涂阴组BALF T-SPOT阳性率无明显差异(χ^2=0.677,P>0.05),但均明显高于非结核组(C2=51.325和51.889,P<0.05)。涂阴肺结核患者BALFT-SPOT检测的ROC曲线下面积为0.932,诊断准确度较高。涂阴患者BALFT-SPOT的敏感性、特异性、阳性预测值(PPV)和阴性预测值(NPV)分别为91.1%、95.2%、98.1%、80%,阳性率明显高于其他结核检测指标。结论利用T-SPOT技术检测BALF中效应性T细胞对于快速诊断涂阴肺结核有较高的临床实用价值。 展开更多
关键词 肺泡灌洗液 涂阴肺结核 T-SPOT 诊断
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自动全站仪的光斑图像中心定位精度分析 预览
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作者 王欣宇 李引生 +2 位作者 杨远程 王彬力 李紫庭 《测绘与空间地理信息》 2019年第1期211-215,共5页
为研制国产的自动目标识别全站仪,自动目标识别与照准全站仪成为研究的热点。本文将CMOS图像传感器内置于RTS010A电动全站仪中,构造自动目标识别全站仪系统。对光斑图像进行处理,提取光斑图像中心点坐标;测试并分析了光斑图像中心定位精... 为研制国产的自动目标识别全站仪,自动目标识别与照准全站仪成为研究的热点。本文将CMOS图像传感器内置于RTS010A电动全站仪中,构造自动目标识别全站仪系统。对光斑图像进行处理,提取光斑图像中心点坐标;测试并分析了光斑图像中心定位精度,全站仪望远镜固定不动时,光斑中心定位精度小于0.2个像素坐标,全站仪望远镜沿水平角或竖直角单方向旋转时,光斑中心坐标变化在固定方向小于0.7个像素坐标。认为光斑图像中心定位精度可满足自动目标识别全站仪模型标定的要求。 展开更多
关键词 全站仪 图像 光斑 中心定位 自动目标识别
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家用空调压缩机铸铁件热节处缩孔的消除方法 预览
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作者 杨忠林 苏建勇 +1 位作者 田超群 徐尔灵 《铸造设备与工艺》 2019年第1期36-38,共3页
家用空调压缩机支架铸铁件热节处容易产生缩孔,内径钻孔后才能发现。通过改进铸件的进水口方向,支架铸件热节处的缩孔单向不良率由5%~10%下降到0.5%左右。结果表明为了消除支架铸件热节处的缩孔,将直浇道直接压在铸件上,补缩效果最为明显。
关键词 工艺 压缩机铸铁件 热节 缩孔
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High-Q, low-mode-volume microsphere-integrated Fabry–Perot cavity for optofluidic lasing applications
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作者 XIAOQIN Wu YIPEI WANG +4 位作者 QIUSHU CHEN YU-CHENG CHEN XUZHOU LI LIMIN TONG XUDONG FAN 《光子学研究:英文版》 CSCD 2019年第1期50-60,共11页
We develop a hybrid optofluidic microcavity by placing a microsphere with a diameter ranging from 1 to 4 μm in liquid-filled plano-plano Fabry–Perot(FP) cavities, which can provide an extremely low effective mode vo... We develop a hybrid optofluidic microcavity by placing a microsphere with a diameter ranging from 1 to 4 μm in liquid-filled plano-plano Fabry–Perot(FP) cavities, which can provide an extremely low effective mode volume down to 0.3–5.1 μm^3 while maintaining a high Q-factor up to 1 × 10^4–5 × 10^4 and a finesse of ~2000. Compared to the pure plano-plano FP cavities that are known to suffer from the lack of mode confinement, diffraction, and geometrical walk-off losses as well as being highly susceptible to mirror misalignment, our microsphere-integrated FP(MIFP) cavities show strong optical confinement in the lateral direction with a tight mode radius of only 0.4–0.9 μm and high tolerance to mirror misalignment as large as 2°. With the microsphere serving as a waveguide, the MIFP is advantageous over a fiber-sandwiched FP cavity due to the open-cavity design for analytes/liquids to interact strongly with the resonant mode, the ease of assembly, and the possibility to replace the microsphere. In this work, the main characteristics of the MIFP, including Q-factor, finesse, effective mode radius and volume, and their dependence on the surrounding medium’s refractive index, mirror spacing, microsphere position inside the FP cavity, and mirror misalignment, are systematically investigated using a finite-element method.Then, by inserting dye-doped polystyrene microspheres of various sizes into the FP cavity filled with water, we experimentally realize single-mode MIFP optofluidic lasers that have a lasing threshold as low as a few microjoules per square millimeter and a lasing spot radius of only ~0.5 μm. Our results suggest that the MIFP cavities provide a promising technology platform for novel photonic devices and biological/chemical detection with ultra-small detection volumes. 展开更多
关键词 mirror radius diameter optical devices down EASE spot
无锌花镀锌板表面灰色斑点的形成原因分析
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作者 袁清 徐光 +2 位作者 戴方钦 郭丽涛 李运成 《材料保护》 CAS CSCD 北大核心 2019年第5期137-142,156共7页
无锌花镀锌板光整后下线时未发现灰色斑点,但放置20余天后表面出现深浅不一的灰色斑点。针对这种表面缺陷,对灰色斑点处镀锌板进行了微观形貌观察与能谱分析。结果表明:镀锌层晶界处含有大量的Fe、O元素,Zn元素较少;正常镀层处Zn元素较... 无锌花镀锌板光整后下线时未发现灰色斑点,但放置20余天后表面出现深浅不一的灰色斑点。针对这种表面缺陷,对灰色斑点处镀锌板进行了微观形貌观察与能谱分析。结果表明:镀锌层晶界处含有大量的Fe、O元素,Zn元素较少;正常镀层处Zn元素较多,Fe元素较少。深浅斑点的出现与镀锌板所处的环境因素以及钝化效果和工艺有关。在一定的环境如高温或潮湿条件下,镀锌板锌粒间成为腐蚀的起点,导致锌层完整性的破坏。其次,钝化效果不好可能导致镀锌板出现钝化层不均匀的现象,造成钝化较薄的区域容易发生表面腐蚀。 展开更多
关键词 无锌花镀锌板 斑点 能谱分析 面扫描 钝化
应用VISIA定量评估APT570nm强脉冲光治疗光老化的疗效 预览
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作者 闫成祥 王喜梅 《中国美容医学》 CAS 2019年第4期62-63,共2页
目的:通过VISIA皮肤测试仪定量评估APT570nm强脉冲光对皮肤光老化的治疗效果。方法:选取2017年9月-2018年6月笔者医院整形外科门诊诊断为光老化并接受APT570nm强脉冲光治疗的女性患者31例,用VISIA皮肤测试仪检测治疗前后皮肤斑点、纹理... 目的:通过VISIA皮肤测试仪定量评估APT570nm强脉冲光对皮肤光老化的治疗效果。方法:选取2017年9月-2018年6月笔者医院整形外科门诊诊断为光老化并接受APT570nm强脉冲光治疗的女性患者31例,用VISIA皮肤测试仪检测治疗前后皮肤斑点、纹理、皱纹、毛孔情况。结果:面部光老化患者经APT570nm强脉冲光治疗后,皮肤斑点值明显下降,差异有显著统计学意义(P<0.01),纹理值、皱纹值下降,差异有统计学意义(P<0.05)。结论:APT570nm强脉冲光对面部皮肤光老化有显著的治疗效果,应用VISIA皮肤检测仪可以进行更加科学直观地评价。 展开更多
关键词 强脉冲光 VISIA皮肤测试仪 光老化 斑点 皱纹 纹理
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应用图像分析技术评价底妆产品的功效性 预览
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作者 底烨 袁登峰 +1 位作者 陆志航 沈佩琳 《日用化学品科学》 CAS 2019年第7期21-25,共5页
介绍了底妆类产品的主要宣称功效的图像评估方法。应用Visia CR采集受试者面部照片,结合图像处理软件Image-Pro Plus7.0分析实验室制备的粉底液在使用前及使用后不同时间点面部皮肤参数,综合评价测试样品的提亮肤色功效、提升肌肤光泽... 介绍了底妆类产品的主要宣称功效的图像评估方法。应用Visia CR采集受试者面部照片,结合图像处理软件Image-Pro Plus7.0分析实验室制备的粉底液在使用前及使用后不同时间点面部皮肤参数,综合评价测试样品的提亮肤色功效、提升肌肤光泽度功效、遮瑕力和持妆力。结果表明,运用图像分析技术可以对底妆产品的多种功效性进行定量评估,为产品宣称以及配方筛选提供客观依据。 展开更多
关键词 图像分析 底妆 提亮肤色 光泽 毛孔 色斑 均一度
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机器人喷涂中输送线停止后的甩点问题解决
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作者 谢巨龙 《现代涂料与涂装》 CAS 2019年第1期12-14,共3页
介绍了在ABB机器人跟踪式喷涂线上,喷涂过程中输送线停止后漆膜上出现油漆点的现象,分析了产生原因,并通过试验进行了改进。
关键词 机器人 喷涂 甩点
Interfacial bonding mechanism in Al/coated steel dissimilar refill friction stir spot welds
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作者 Z. Shen Y. Ding +4 位作者 J. Chen B. Shalch Amirkhiz J.Z. Wen L. Fu A.P. Gerlich 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2019年第6期1027-1038,共12页
Defect-free dissimilar Al/zinc coated steel and Al/AlSi coated steel welds were successfully fabricated by refill friction stir spot welding. However, Al alloy and uncoated steel could not be welded under the same wel... Defect-free dissimilar Al/zinc coated steel and Al/AlSi coated steel welds were successfully fabricated by refill friction stir spot welding. However, Al alloy and uncoated steel could not be welded under the same welding condition. Al-Zn eutectic layer formed at the Al/zinc coated steel interface showed nonuniformity in thickness and nanoscale intermetallic(IMC) produced was discontinuous. The bonding formation between the Al-Zn layer and the surrounding materials was attributed to a liquid/solid reaction mechanism. Bonding formation at Al alloy and AlSi coated steel interface was attributed to a solid/solid reaction mechanism, as the joining process did not involve with melting of base metals or AlSi coating materials. Kissing bond formed at the weld boundary acted as a crack initiation and propagation site,and the present study showed that weld strength of Al 5754/AlSi coated steel was greatly influenced by properties of original IMC layer. 展开更多
关键词 REFILL FRICTION STIR spot welding Al alloy STEEL Coated materials Joining MECHANISM
Frictio n stir spot welding of SPCC low carb on steel plates at extremely low welding temperature
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作者 Y.F.Sun H.Fujii +1 位作者 Y.Sato Y.Morisada 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2019年第5期733-741,共9页
Friction stir spot welding (FSSW) was applied to 2.0 mm thick steel plate cold-rolled commercial (SPCC) low carbon steel plates at a very low rotation speed that ranged from 5 to 50rpm, which was much lower than that ... Friction stir spot welding (FSSW) was applied to 2.0 mm thick steel plate cold-rolled commercial (SPCC) low carbon steel plates at a very low rotation speed that ranged from 5 to 50rpm, which was much lower than that generally used for the conventional FSSW technique. Due to the very low heat input, the welding processes could therefore be completed at a peak welding temperature below 160℃. As a result, a significantly refined microstructure with an average grain size of about 0.41μm was formed in the stir zone of the joints and the JI {0-11 }<-211> and J2{1-1O}<-1-12> shear textures were the dominant components, which are different from the D1{11-2}<111> and D2{-1-12}<111> shear textures formed in the conventional FSSW joints. In addition, no heat affected zone could be detected along the crosssectional plane of the joints. Although a few void-like non-bonded areas were still observed along the interface between the upper and lower steel plates, the shear tensile loads of the joints increased to about 10.0 kN when welded at a condition of 8t, 20rpm and 30 s, and the joints fractured through the plug failure mode. 展开更多
关键词 Friction STIR SPOT welding Dynamic RECRYSTALLIZATION Microstructure Steel
Effect of retained austenite and nonmetallic inclusions on the thermal/electrical properties and resistance spot welding nuggets of Si-containing TRIP steels 预览
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作者 V.H.Vargas I.Mejía +1 位作者 V.H.Baltazar-Hernández C.Maldonado 《矿物冶金与材料学报:英文版》 SCIE EI CAS CSCD 2019年第1期52-63,共12页
Five advanced high-strength transformation-induced plasticity(TRIP)steels with different chemical compositions were studied to correlate the retained austenite and nonmetallic inclusion content with their physical pro... Five advanced high-strength transformation-induced plasticity(TRIP)steels with different chemical compositions were studied to correlate the retained austenite and nonmetallic inclusion content with their physical properties and the characteristics of the resistance spot welding nuggets.Electrical and thermal properties and equilibrium phases of TRIP steels were predicted using the JMatPro software.Retained austenite and nonmetallic inclusions were quantified by X-ray diffraction and saturation magnetization techniques.The nonmetallic inclusions were characterized by scanning electron microscopy.The results show that the contents of Si,C,Al,and Mn in TRIP steels increase both the retained austenite and the nonmetallic inclusion contents.We found that nonmetallic inclusions affect the thermal and electrical properties of the TRIP steels and that the differences between these properties tend to result in different cooling rates during the welding process.The results are discussed in terms of the electrical and thermal properties determined from the chemical composition and their impact on the resistance spot welding nuggets. 展开更多
关键词 transformation-induced plasticity steel retained austenite non-metallic inclusions magnetic saturation electrical PROPERTIES THERMAL PROPERTIES resistance spot welding NUGGET
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应用于空间精密测量的全玻璃光纤耦合器的系统设计 预览
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作者 赵亚 姚东 +2 位作者 王智 方超 李钰鹏 《中国光学》 CAS CSCD 北大核心 2019年第3期432-440,共9页
本文提出了一种全玻璃材料的光纤耦合器以实现高精度,高稳定的干涉测量。首先,介绍了干涉测量系统的工作原理以及光纤耦合器的系统设计,然后通过理论分析选取了非球面透镜,并根据具体的透镜参数进行了数值分析以及软件分析。接着进行了... 本文提出了一种全玻璃材料的光纤耦合器以实现高精度,高稳定的干涉测量。首先,介绍了干涉测量系统的工作原理以及光纤耦合器的系统设计,然后通过理论分析选取了非球面透镜,并根据具体的透镜参数进行了数值分析以及软件分析。接着进行了光束参数匹配度以及光束矢量匹配度的容差分析以及结构的热分析。最后结合理论分析以及精密的装调手段完成了光纤耦合器的制作。实验结果表明:光斑尺寸相对于仿真结果的误差约为3.4%,两光斑尺寸差异为0.9%,偏心距离低于40μm,夹角约为60μrad,基本满足干涉测量系统的使用要求。 展开更多
关键词 空间引力波探测 干涉测量 光纤耦合器 光斑
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三种实验方法检测胸腔积液对结核性胸膜炎的诊断价值分析 预览
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作者 王少华 杨翰 +1 位作者 李爱芳 崔晓利 《现代检验医学杂志》 CAS 2019年第3期104-108,共5页
目的探讨GeneXpert MTB/RIF实验、结核感染T细胞斑点试验(T-SPOT.TB)以及结核分枝杆菌液体培养在结核性胸膜炎诊断中的价值。方法选取临床已经确诊结核性胸膜炎的患者142例和非结核性胸膜炎患者51例,对其胸腔积液样本分别进行GeneXpert ... 目的探讨GeneXpert MTB/RIF实验、结核感染T细胞斑点试验(T-SPOT.TB)以及结核分枝杆菌液体培养在结核性胸膜炎诊断中的价值。方法选取临床已经确诊结核性胸膜炎的患者142例和非结核性胸膜炎患者51例,对其胸腔积液样本分别进行GeneXpert MTB/RIF检测、T-SPOT.TB以及结核分枝杆菌培养,分析比较三种方法并联和串联对结核性胸膜炎的诊断价值。结果结核性胸膜炎患者T-SPOT.TB的阳性率显著高于其他两种方法。GeneXpert MTB/RIF检测、T-SPOT.TB以及结核分枝杆菌培养的敏感度分别为16.9%,81.0%和24.6%,特异度分别为98.0%,33.3%和86.3%,其中T-SPOT.TB试验的敏感度最高,特异度最小。三种方法串联后形成的四种不同方案的敏感度均低于19%,特异度均高于90%。三种方法并联后形成的四种不同方案的敏感度存在差异,其中GeneXpert MTB/RIF检测与结核培养试验并联方案的敏感度为29.6%,显著低于其他三种方案,其特异度为86.3%,显著高于其他三种方案。结论在结核性胸膜炎诊断中,T-SPOT.TB试验具有较高的敏感度,而GeneXpert MTB/RIF检测以及结核分枝杆菌培养具有较高的特异度;三者不同串联方案均具有很高的特异度;并联方案中,GeneXpert MTB/RIF检测与结核培养试验并联的诊断特异度最高,对通过胸腔积液诊断结核性胸膜炎提供重要参考价值。 展开更多
关键词 结核性胸膜炎 GeneXpert MTB/RIF 结核感染T细胞斑点试验 结核分枝杆菌
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支气管扩张合并非结核分枝杆菌感染临床分析 预览
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作者 郑艳 周华 周建英 《中国感染与化疗杂志》 CAS CSCD 北大核心 2019年第3期253-258,共6页
目的探讨支气管扩张(支扩)合并非结核分枝杆菌(nontuberculosis mycobacteria,NTM)感染患者的临床特点和肺部影像表现。方法回顾性分析浙江大学医学院附属第一医院2016年6月-2018年6月确诊为支扩合并NTM感染的患者,收集患者临床、微生... 目的探讨支气管扩张(支扩)合并非结核分枝杆菌(nontuberculosis mycobacteria,NTM)感染患者的临床特点和肺部影像表现。方法回顾性分析浙江大学医学院附属第一医院2016年6月-2018年6月确诊为支扩合并NTM感染的患者,收集患者临床、微生物学、影像等资料。结果共有40例患者诊断为支扩合并NTM感染,其中27例感染Ⅲ组分枝杆菌,均为鸟-胞内分枝杆菌复合群(Mycobacterium avium complex,MAC),占67.5%(27/40);11例感染Ⅳ组分枝杆菌,均为龟-脓肿分枝杆菌复合群,占27.5%(11/40);2例感染Ⅱ组分枝杆菌,均为堪萨斯分枝杆菌,占5.0%(2/40)。龟-脓肿分枝杆菌复合群的患者出现咯血症状的比例明显高于MAC感染的患者(χ^2=8.212,P=0.004),MAC则以胸闷气促、发热常见。NTM感染的支扩患者痰抗酸杆菌涂片阳性率高达86.8%,痰液NTM-DNA检测阳性率较高(89.4%),而血结核感染T细胞检测(T-SPOT)常阴性(94.1%)。支扩合并NTM感染的肺部影像中空洞、小结节、树芽征、斑片状渗出影常见,MAC组的支扩则常侵犯双上叶、中叶或舌叶。结论支扩合并NTM感染以MAC和龟-脓肿分枝杆菌复合群为常见;两者临床表现有差异,其中龟-脓肿分枝杆菌复合群组咯血发生率更高;影像表现多样,MAC组支扩以右肺中叶支气管最好发。 展开更多
关键词 支气管扩张 非结核分枝杆菌 结核感染T细胞检测 非结核分枝杆菌-DNA
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Optimization of resistance spot brazing process parameters in AHSS and AISI 304 stainless steel joint using filler metal 预览
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作者 Niwat Mookam 《Defence Technology(防务技术)》 CAS CSCD 2019年第3期450-456,共7页
The aim of this research study was to determine optimal resistance spot brazing parameters for joining between AHSS and AISI 304 stainless steel by using filler metal. The key parameters investigated in this study con... The aim of this research study was to determine optimal resistance spot brazing parameters for joining between AHSS and AISI 304 stainless steel by using filler metal. The key parameters investigated in this study consist of the brazing current, electrode pressure and brazing time. The Taguchi method was applied to the design of experiments. Signal-to-Noise ratio was introduced in the study to identify optimal levels from the process where input parameters yield increased shear strength. Brazing was thus implemented with 5,000A brazing current, 0.70 MPa electrode pressure, and 1.50s brazing time. The maximum shear strength obtained was 54.31 N·mm^-2 in accordance with input parameter settings. In addition, Cu-rich phase and Ag0.4Fe0.6 intermetallic phases were found at the interface zone. 展开更多
关键词 RESISTANCE SPOT brazing FILLER metal AHSS STAINLESS steel INTERMETALLIC phases
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Effect of electrode morphology on steel/aluminum alloy joint 预览
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作者 张月莹 孙大千 +1 位作者 苏雷 柳艳军 《中国焊接:英文版》 EI CAS 2019年第1期16-27,共12页
Microstructure characteristics of dissimilar-metal resistance spot welded joints of SUS301L austenitic stainless steel and 6063-T6 aluminum alloy, and effects of electrode morphology were studied. Results indicated th... Microstructure characteristics of dissimilar-metal resistance spot welded joints of SUS301L austenitic stainless steel and 6063-T6 aluminum alloy, and effects of electrode morphology were studied. Results indicated that welded joints of dissimilar materials between austenitic stainless steel and aluminum alloy had characteristics of welding-brazing. The aluminum nugget consisted mainly of the cellular crystal, cellular dendrites and dendrites. The interface between austenitic stainless steel and aluminum alloy had a two-layered structures:a flat front surface θ-Fe 2 Al 5 on the steel side and a serrated morphology θ-FeAl 3 on the aluminium alloy side, and it was the weakest zone of the joints. The electrode morphology had great effects on spot welded joints of stainless steel and aluminum alloy. The custom electrodes were a planar circular tip electrode with tip diameter of 10 mm on the stainless steel side and a spherical tip electrode with spherical radius of 35 mm on the aluminum alloy side. When the custom electrodes were used, the nugget diameter, tensile shear load and indentation ratio of spot welded joint were 7.22 mm, 3 606 N and 10.71%, respectively. The nugget diameter and joint tensile shear load increased by 34% and 102% respectively, and the indentation ratio decreased by 65% compared with the F-type electrodes (nugget diameter: 5.384 mm, tensile-shear load 1 783 N, indentation rate 30.94%). Therefore, it was more favorable to use the custom electrodes for improving the mechanical properties and appearance quality of resistance spot welded joints of stainless steel and aluminum alloy. 展开更多
关键词 aluminium alloy STAINLESS STEEL resistance SPOT welding MICROSTRUCTURES mechanical properties
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Investigation of Mechanical Properties of Friction Stir Spot Welded Light Metal Alloys 预览
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作者 Ahmet Atak Aydin Sik 《机械工程与自动化:英文版》 2019年第2期56-63,共8页
The use of light metals today is of great importance,for example in the automotive,aviation and aerospace industries,where energy consumption is minimized and thus the economy is being attempted.By using light metals,... The use of light metals today is of great importance,for example in the automotive,aviation and aerospace industries,where energy consumption is minimized and thus the economy is being attempted.By using light metals,weight is reduced so that energy is saved.Aluminum and magnesium alloys are particularly used thanks to their lightweight.Vehicles in the automotive,aerospace and space industries are expected not only to have lightweight but also high static and dynamic strengths since they are exposed to static and dynamic cyclic loads.However,the structural components can quickly become fatigued and fail under cyclic load due to the notch factor of the joining zones.Compared to the fusion welding method,joining of material is realized mechanically below the melting point of the material in the friction stir spot welding(FSSW)method.Thus,the fatigue strength of the assembly is much higher than that of the fusion welding.In this study,light metal alloy of magnesium AZ31B and aluminum EN AW 2024 were joined with FSSW method and mechanical properties of this joins were also carried out. 展开更多
关键词 FRICTION STIR SPOT WELDING joining of MAGNESIUM joining of aluminum WELDING of light metals.
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小龙虾真菌病害(二):灼斑病 预览
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作者 赵楠 巫爱军 赵桂华 《水产养殖》 CAS 2019年第5期43-46,共4页
小龙虾灼斑病(burn spot disease),又被称为真菌甲壳溃疡病(fungal shell canker disease),在世界各地是最常见、分布最广和危害较重的甲壳动物病害之一[1]。
关键词 真菌病害 小龙虾 斑病 甲壳溃疡病 SPOT 甲壳动物
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汽车涂装生产过程中脏点分析及控制 被引量:1
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作者 吴忠喜 《现代涂料与涂装》 CAS 2018年第5期46-48,52共4页
通过对现场的取样分析,分析了主要脏点类型,同时从人、机、料、法、环5个方面对脏点产生的原因进行了剖析、通过对各个生产环节进行优化和现场管理的改善,使脏点问题大大改善,从而提升了车身的一次交检合格率。
关键词 汽车涂装 脏点 脏点分析 现场管理 改善措施
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