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Aluminum Electroplating on AZ31 Magnesium Alloy with Acetic Anhydride Pretreatment

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Acta Metallurgica Sinica(English Letters) 2022年第12期35卷 1996-2006页

Magnesium(Mg)alloys for metal electroplating require a surface pretreatment,i.e.,the removal of the spontaneously oxidized surface layer(MgO,Mg(OH)_(2),andMgCO_(3)).However,the use of highly toxic and/or corrosive acids in conventional pretreatment processes has become an *** this study,a facile and less toxic pretreatment is demonstrated and applied in aluminum(Al)*** immersion of the AZ31 Mg alloy into acetic anhydride(Ac_(2)O)removed the spontaneously oxidized surface layer and formed a thin but stable magnesium acetate(Mg(OAc)_(2))layer that protects the metal substrate from further *** Al electroplating bath is a concentrated diglyme(G2)-AlCl_(3)organic solution that can readily dissolve Mg(OAc)_(2)to enable direct plating onto a metal *** as-deposited Al layer has a compact and crack-free morphology that improves the corrosion resistance and hardness(2.7 GPa).Owing to the lack of an interfacial oxidized layer,heat treatment led to the successful diff usion of Mg and Al atoms,which increased the hardness to 4.4 *** Ac_(2)O pretreatment of Mg alloys enables the successful Al electroplating and subsequent heat treatment.

关键词： Magnesium alloy Surface modifi cation Electrodeposition Hardness Corrosion resistance

A passive optical fibre sensor based on Fabry-Perot interferometry for bipolar electrostatic monitoring of insulating dielectrics

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High Voltage 2023年第4期8卷 682-689页

作者： Jiawei zhang Zifan Ye Li Wang zelei zhang Fan Xu Weichen Dang Takao Matsumoto Sombel Diaham Chatchai Putson School of Electrical Engineering Xi'an University of TechnologyXi'anShaanxiChina Universitéde Toulouse UPSINPTLAPLACE(Laboratoire Plasma et Conversion d'Energie)Toulouse Cedex 9France Materials Physics Laboratory Department of PhysicsFaculty of SciencePrince of Songkla University(PSU)SongkhlaThailand

The measurement of the surface charge on the insulating dielectrics is critical to estimate the insulation strength of electrical equipment in *** interactions with the electromagnetic field,however,generally result in distortion measurement of active ***,it is of great significance to investigate a passive sensor for monitoring the deposited ***,a passive optical fibre electrostatic sensor is developed on the principle of Fabry–Perot interference to quantify the surface potential of the insulating *** sensitivity of quantifying the electrostatic charge is explored in terms of the wavelength shift in the interference spectrum,and the linear correlation is ***,the sensor can identify a negative quadratic trend with the increase of the surface roughness of the insulating *** merits of the proposed sensor such as passive monitoring,bipolar electrostatic detection,and the excellent ability of antielectromagnetic interference are highlighted in the ***,this sensor can serve as an effective tool to monitor the electrostatic charge in the fields of smart electrical equipment,fuel transportation,aerospace,integrate circuit etc.

关键词： electrostatic passive fibre

Influence of shape effect on dynamic surface charge transport mechanism of cellular electret after corona discharge

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Plasma Science and Technology 2022年第4期24卷 82-88页

作者： Jiawei zhang zelei zhang T MATSUMOTO Qingqing GAO Yuanye LIU K NISHIJIMA Yifan LIU School of Electrical Engineering Xi'an University of TechnologyXi'an 710048People's Republic of China Faculty of Engineering Fukuoka UniversityFukuoka 814-0180Japan Xi'an Jiaotong University Xi'an 710049People's Republic of China

Surface charge accumulation and transport on cellular polypropylene play an important role in nanogenerators,which could have a potential impact on energy harvesting and wearable devices for zero carbon energy systems and the internet of *** shapes have different charge accumulation and decay characteristics of the ***,we studied the influence of the sample’s shape on the surface charge decay by experiment and *** surface potential of square and circular cellular polypropylene was measured by a two-dimensional surface potential measurement system with electrostatic capacitive *** experimental result shows that the surface potential distribution of the square sample dissipates non-uniformly from the bell shape to a one-sided collapsed shape,while that of the circular sample dissipates uniformly from the bell shape to the crater-like ***,the simulated results of the initial surface potential distributions of the square and circular cellular polypropylene are consistent with the experimental *** investigation demonstrates that the charge transport process is correlated with the shape of the sample,which provides significant reference for designing electret material used for highly efficient nanogenerators.

关键词： charge transport nanogenerator corona discharge simulation shape effect cellular polypropylene sustainable energy

Diagnostic Value of Neutrophil-Lymphocyte Ratio and Platelet-Lymphocyte Ratio in Patients with Severe COVID-19—7 PLADs,China,January 21–February 10,2020

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China CDC weekly 2022年第10期4卷 195-198,I0001页

作者： Yan Ma Dongshan Zhu Nannan Shi Lei zhang Guangkun Chen Youwen Ge zelei zhang Renbo Chen Sihong Liu Yipin Fan Huamin zhang Yanping Wang Department of Infectious Disease Prevention Institute of Basic Research in Clinical MedicineChina Academy of Chinese Medical SciencesBeijingChina Department of Epidemiology School of Public HealthCheeloo College of MedicineShandong UniversityJinanShandong ProvinceChina Jinan250012China Chinese Medicine Standardization Research Center Institute of Basic Research in Clinical MedicineChina Academy of Chinese Medical SciencesBeijingChina Institute of Information on Traditional Chinese Medicine China Academy of Chinese Medical SciencesBeijingChina Institute of Chinese Materia Medica China Academy of Chinese Medical SciencesBeijingChina.

Summary What is already known about this topic?Coronavirus disease 2019(COVID-19)causes symptoms ranging from mild to *** for identifying severe COVID-19 infection have not been well identified,especially for young *** is added by this report?Both neutrophil-lymphocyte ratio(NLR)[area under curve(AUC):0.80;the odds ratios(OR)and 95%confidence intervals(95%CI):1.30(1.13–1.50)]and platelet-lymphocyte ratio(PLR)[AUC:0.87;OR(95%CI):1.05(1.01–1.09)]were determined to be indicators for recognition of patients with severe COVID-19 in young patients less than age *** are the implications for public health practice?NLR and PLR are useful indicators for identifying patients with severe COVID-19,especially in young patients less than age 40.

关键词： Lymphocyte Patients Platelet

一种改性纳米SiO_(2)/聚合物复合材料涂层的制备

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装备制造与教育 2023年第2期37卷 50-53,94页

作者：尹才洪张泽磊四川工程职业技术学院材料系四川德阳618000

利用纳米SiO_(2)和三种单体:2-丙烯酰胺基-2-甲基-1-丙烷磺酸(AMPS)、N-乙烯吡咯烷酮(NVP)与丙烯酸(AA)作为原料,使用化学手段合成了纳米SiO_(2)/聚合物。利用傅里叶变换红外光谱(FTIR)方法对合成物中的成分进行了测定。利用电化学阻抗... 详细信息

利用纳米SiO_(2)和三种单体:2-丙烯酰胺基-2-甲基-1-丙烷磺酸(AMPS)、N-乙烯吡咯烷酮(NVP)与丙烯酸(AA)作为原料,使用化学手段合成了纳米SiO_(2)/聚合物。利用傅里叶变换红外光谱(FTIR)方法对合成物中的成分进行了测定。利用电化学阻抗谱、动电位极化曲线、扫描电子显微镜-能谱仪、研究了不同浓度的该复合材料涂层对N80钢在3.5wt.%NaCl溶液中的表面形貌和耐蚀性能。结果表明:合成的纳米SiO_(2)/聚合物复合材料在3.5wt.%NaCl溶液中对N80钢具有优良的腐蚀抑制效果,当含量为800ppm时,通过电化学交流阻抗谱得到的缓蚀效率达到93.27%。

关键词：改性纳米SiO_(2) CO_(2)腐蚀电化学

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一种结晶器非正弦振动模型的构建及其应用

铸造技术 2014年第5期35卷 1081-1084页

作者：张伟张泽磊四川工程职业技术学院四川德阳618000

以正弦振动波形为基础,利用分段函数法构造出一种非正弦振动波形,经公式推导,得出非正弦振动的6个振动工艺参数表达式。在此基础上,对工厂实际中某一型号连铸结晶器的6种振动方式进行了波形解析。

关键词：非正弦振动波形工艺参数波形拟合

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碳氢火灾下钢桁-混凝土组合梁耐火试验研究

建筑结构学报 2024年第3期45卷 160-173页

作者：汤陈皓张岗李徐阳陆泽磊宋超杰王世超长安大学公路学院陕西西安710064

为研究钢桁-混凝土组合结构桥梁的耐火性能,开展了三榀简支下承式钢桁-混凝土组合模型梁的碳氢火灾试验。采集测点的时变温度,获得模型梁的温度场和传热模式;分析关键断面挠度变化规律和模型梁的破坏模式,揭示热-力耦合作用下的结构响... 详细信息

为研究钢桁-混凝土组合结构桥梁的耐火性能,开展了三榀简支下承式钢桁-混凝土组合模型梁的碳氢火灾试验。采集测点的时变温度,获得模型梁的温度场和传热模式;分析关键断面挠度变化规律和模型梁的破坏模式,揭示热-力耦合作用下的结构响应和破坏机理。研究结果表明:热-力耦合作用会使混凝土桥面板产生大量裂缝,并从中释放水蒸气,在裂缝较少的区域则会出现由于混凝土内部水蒸气压力过大导致的混凝土爆裂现象;混凝土板的隔火作用会使模型梁的温度场呈现出显著的分层现象,并在主桁斜杆高度方向上引起显著的温度梯度效应;横、纵梁下翼板会阻隔部分火焰,形成热辐射盲区,呈现出干扰式传热效应;模型梁的挠度历程可分为初增、缓增和急增3个阶段,当跨中挠度达到L/28后,难以持荷,可认为模型梁达到极限状态,表现为大挠度破坏;当外荷载水平降低10%、模型梁桁架高度增大25%时,分别可将耐火时间提高44.7%和33.3%。建立了经耐火试验验证的热-力-结构耦合数值分析模型,提出了针对钢桁-混凝土组合梁的四阶段损伤-破坏路径及其特征。

关键词：钢桁-混凝土组合梁碳氢火灾耐火试验数值模拟耐火性能

Y_2O_3添加对Cu-W合金显微组织和性能的影响

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铸造技术 2015年第2期36卷 471-474页

作者：张伟张泽磊张晋涛四川工程职业技术学院材料工程系四川德阳618000

研究了Y2O3添加对Cu-W合金显微组织和性能的影响。结果表明,混合粉末经过裂解、还原后颗粒尺寸得到显著细化。随着Y2O3添加量的增加,烧结试样中钨相尺寸逐渐减小。Y2O3的含量为0.4%时组织中的钨相分布最为均匀,烧结颈形成良好。但随着Y... 详细信息

研究了Y2O3添加对Cu-W合金显微组织和性能的影响。结果表明,混合粉末经过裂解、还原后颗粒尺寸得到显著细化。随着Y2O3添加量的增加,烧结试样中钨相尺寸逐渐减小。Y2O3的含量为0.4%时组织中的钨相分布最为均匀,烧结颈形成良好。但随着Y2O3含量的继续增加,钨颗粒自身及Y2O3的团聚倾向均增加,组织中出现孔洞。且Cu-W合金的硬度、电导率均逐渐减小。

关键词： Cu-W触头材料稀土氧化物液固掺杂法

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AZ91D镁合金的冷却凝固特性研究

热加工工艺 2010年第1期39卷 47-49页

作者：张泽磊杨刚杨屹卢东四川大学制造科学与工程学院四川成都610065

采用DSC对AZ91D镁合金的冷却凝固特性进行了研究。研究发现,AZ91D镁合金的液相线温度为595℃,固相线温度为470℃,液、固相线温度差为125℃,属于宽结晶温度范围低熔点合金。该合金的平均自由线收缩率为1.572%,冷却凝固时倾向于体积凝固方... 详细信息

采用DSC对AZ91D镁合金的冷却凝固特性进行了研究。研究发现,AZ91D镁合金的液相线温度为595℃,固相线温度为470℃,液、固相线温度差为125℃,属于宽结晶温度范围低熔点合金。该合金的平均自由线收缩率为1.572%,冷却凝固时倾向于体积凝固方式,容易形成粗大的离异共晶组织。

关键词： AZ91D镁合金差示扫描量热法冷却凝固特性