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基于PLC的医用电梯控制系统的设计

自动化应用 2024年第3期65卷 92-94页

作者：范建锋苏州高等职业技术学校江苏苏州215000

与传统电梯控制系统相比,医用电梯控制系统需更注重电梯升降过程的平稳性,以保证患者的舒适度,因此,需设计医用电梯控制系统。首先,采用西门子S7-1200系列PLC作为主控制单元,采用ACS880变频器驱动曳引电机与门电机。然后,通过梯形图的... 详细信息

与传统电梯控制系统相比,医用电梯控制系统需更注重电梯升降过程的平稳性,以保证患者的舒适度,因此,需设计医用电梯控制系统。首先,采用西门子S7-1200系列PLC作为主控制单元,采用ACS880变频器驱动曳引电机与门电机。然后,通过梯形图的编译实现呼叫应答、平层开关检测、目标楼层的运行和停止等功能。最后,增加电梯运行安全保护功能,一旦出现危险情况可立即报警。经测试,该系统稳定可靠、调速平滑、安全性高,可应用于各种医用环境。

关键词：医用电梯变频器 PLC控制

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阿托品治疗肥厚性幽门狭窄的研究进展

临床小儿外科杂志 2024年第5期23卷 485-488页

作者：周燕樊剑锋程明南京医科大学附属无锡人民医院新生儿外科，无锡214023

肥厚性幽门狭窄(hypertrophic pyloric stenosis,HPS)是由于幽门肌增生肥厚引起的胃出口梗阻性疾病,其发病机制尚未完全清楚,可能继发于幽门肌的持续性痉挛或失弛缓。阿托品作为M胆碱能受体阻断剂,能解除幽门肌痉挛,被用于HPS的保守治... 详细信息

肥厚性幽门狭窄(hypertrophic pyloric stenosis,HPS)是由于幽门肌增生肥厚引起的胃出口梗阻性疾病,其发病机制尚未完全清楚,可能继发于幽门肌的持续性痉挛或失弛缓。阿托品作为M胆碱能受体阻断剂,能解除幽门肌痉挛,被用于HPS的保守治疗。阿托品治疗HPS,最早采用口服给药,近年来又采用静脉注射给药。阿托品静脉注射治疗HPS,采取序贯用药的方式疗效较好,是HPS保守治疗的新方法。本文就阿托品治疗HPS的新进展进行综述。

关键词：肥厚性幽门狭窄阿托品

风电场风机基础大体积混凝土冬季施工技术探讨

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红水河 2024年第4期43卷 90-93页

作者：樊建峰林运胜周熙中国安能集团第一工程局有限公司广西南宁530200

为解决大体积混凝土冬季施工存在的物理力学性能降低、黏结力下降等问题,以辽宁鞍山海城150 MW风电项目为例,笔者分析大体积混凝土冬季施工难点,探讨施工技术要点及优化措施。通过采用二次投料法抗冻混凝土搅拌工艺、低温抗冻泵送混凝... 详细信息

为解决大体积混凝土冬季施工存在的物理力学性能降低、黏结力下降等问题,以辽宁鞍山海城150 MW风电项目为例,笔者分析大体积混凝土冬季施工难点,探讨施工技术要点及优化措施。通过采用二次投料法抗冻混凝土搅拌工艺、低温抗冻泵送混凝土运输和浇筑技术,做好抗冻混凝土养护,能够有效保证混凝土施工质量。

关键词：大体积混凝土冬季施工施工技术风机基础风电场

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航天器大功率固态配电关键技术研究

航天器工程 2024年第3期33卷 40-47页

作者：赵建伟李化义张明范建锋董浩轩黄雷刘俊尧哈尔滨工业大学卫星技术研究所哈尔滨150080 山东航天电子技术研究所山东烟台264670 北京空间飞行器总体设计部北京100094

大功率固态配电需要解决在开关过程中电压变化率和电流变化率较高的问题,抑制在短路保护过程中功率管漏极和源极存在的振荡和高电压应力。采用“慢开通,慢关断”的控制方式,降低了开通和关断过程中的电压和电流变化率。通过降低关断过... 详细信息

大功率固态配电需要解决在开关过程中电压变化率和电流变化率较高的问题,抑制在短路保护过程中功率管漏极和源极存在的振荡和高电压应力。采用“慢开通,慢关断”的控制方式,降低了开通和关断过程中的电压和电流变化率。通过降低关断过程中电流变化率和增大振荡回路阻尼的方法,抑制了短路保护关断过程中功率管漏源电压应力和振荡。在此基础上,研制了160 V/200 A固态配电样机,实验验证表明所采用的方法是有效的。该方法提高了大功率负载的配电可靠性,可为大功率固态配电在航天领域的应用提供参考。

关键词：航天器电源系统大功率固态配电高可靠性短路保护

The aging behavior,microstructure and mechanical properties of AlN/AZ91 composite

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镁合金学报(英文) 2023年第7期11卷 2458-2468页

作者： Yunxia Sun Changlin Yang Bin Zhang jianfeng fan Hongxiang Li Tianhao Zhao Jing Li State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’anShaanxi 710072PR China Yangtze River Delta Research Institute of NPU TaicangJiangsu 215400PR China Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024PR China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083PR China

Microstructure evolution and mechanical properties of the aging treated AlN/AZ91 composites were systematically investigated by optical microscopy(OM),high resolution scanning electron microscopy(HRSEM)with an energy dispersive spectrum(EDS),and high-angle annular dark field scanning transmission electron microscopy(HAADF-STEM).The results show that the higher fracture elongation(14±1%)and ultimate tensile strength(275±6 MPa)were simultaneously obtained in the peak-aged AlN/AZ91 *** with AZ91 matrix alloy,the strength was increased by about 44%and the elongation was approximately five times higher,which mainly attributed to the precipitation of nano-sizedγ-Mg_(17)Al_(12)phase and the activation of non-basal slip systems induced by in-situ AlN particles at room ***,the in-situ formation of AlN reinforcements consumed part of Al element in the matrix alloy,which resulted into the volume fraction decreasing ofγ-Mg_(17)Al_(12)precipitates,and then the age hardening and strengthening efficiency were reduced in the AlN/AZ91 *** the other hand,the mismatch of thermal expansion coefficient between AlN particles and AZ91 matrix generated high density dislocations around AlN particles,which promoted the precipitation ofγ-Mg_(17)Al_(12)phase,and then the peak aging time and temperature were decreased.

关键词： Magnesium matrix composites In-situ AlN particles Aging behavior Microstructure Mechanical properties

Effect of electropulsing treatment on static recrystallization behavior of cold-rolled magnesium alloy ZK60 with different reductions

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Journal of Materials Science & Technology 2019年第6期35卷 1113-1120页

作者： Huijun Guo Xun Zeng jianfeng fan Hua Zhang Qiang Zhang Weiguo Li Hongbiao Dong Bingshe Xu Key Laboratory of Interface Science and Engineering in Advanced Materials. Ministry of Education Taiyuan University of Technology Taiyuan 030024China Shanxi Key Laboratory of Advanced Magnesium-Based Materials Taiyuan 030024 China Shanxi Research Center of Advanced Materials Science and Technology Taiyuan 030024 China Department of Engineering University of Leicester Leicester LEI 7RH UK

Effect of electropulsing treatment(EPT) on recrystallization behavior of cold-rolled Mg alloy ZK60 strips was investigated. It was found that EPT significantly improved nucleation rate and migration ability of grain boundaries, leading to accelerated recrystallization of the deformed metals at relatively low temperature. After the recrystallization induced by EPT, the average grain size of 20% rolling reduction samples decreased from 113 um to around 10 um, meanwhile the typical basal-type texture of the coldrolled sample was weakened. EPT was normally accompanied with a thermal and an athermal effects. The athermal effect played a dominated role in increasing nucleation rate, while the thermal effect promoted grain growth. A fewer recrystallized grains originated along the grain boundaries in the 10% reduction samples, while most of the recrystallization took place inside the twins in the 20% reduction samples.

关键词： Mg alloys Recrystallization Athermal effect Twins

Effect of Extrusion Combination Types on Microstructure and Mechanical Properties of the AZ31/GW103K Bimetallic Composite Plates

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Acta Metallurgica Sinica(English Letters) 2022年第12期35卷 1959-1972页

作者： Yunpeng Meng Boyu Lin Lifei Wang jianfeng fan Shangzhou Zhang Liwei Lu Hans Jφrgen Roven Hua Zhang Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024China Institute for Advanced Studies in Precision Materials Yantai UniversityYantai 264005China Hunan Provincial Key Laboratory of High Efficiency and Precision Machining of Difficult-to-Cut Material Hunan University of Science and TechnologyXiangtan 411201China Department of Materials Science and Engineering Norwegian University of Science and Technology7491 TrondheimNorway

The AZ31/GW103 K bimetallic composite plates were prepared by co-extrusion of different combination types(sandwich extrusion type and double semicircle extrusion type),and effects of different extrusion combination types on the microstructure and mechanical properties of bimetallic composite plates were systematically *** results show that both the AZ31/GW103 K bimetallic composite plates prepared by different extrusion combination types have good metallurgical bonding,and changing the combination type does not affect the thickness of the interfacial transition layer of composite *** with the monolithic AZ31 and GW103 K extruded plates,co-extrusion can promote the dynamic recrystallization(DRX)of AZ31 and GW103 K components in composite plates,and double semicircular extrusion type has a better promotion effect on the DRX than sandwich extrusion *** addition,the texture of AZ31 in both monolithic AZ31 and AZ31/GW103 K/AZ31(A/G/A)plates is a typical(0002)basal texture,while that in the AZ31/GW103 K(A/G)composite plate shifts to the tangent direction(TD)of extruded *** with the monolithic AZ31 extruded plate,both the yield strength and tensile strength of A/G and A/G/A bimetallic composite plates are significantly *** strength of A/G/A composite plate is higher than that of A/G composite plate,but its elongation is ***,co-extrusion reduces the dislocation density of AZ31 and GW 103 K components in composite plates,and different extrusion combination types also affect the dislocation density.

关键词： Bimetallic composite plates Extrusion combination types Dynamic recrystallization Dislocation density Mechanical behavior

Extraordinary mechanical properties of AZ61 alloy processed by ECAP with 160° channel angle and EPT

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Journal of Magnesium and Alloys 2021年第2期9卷 548-559页

作者： Zhaohui Shan Jie Yang jianfeng fan Hua Zhang Qiang Zhang Yucheng Wu Weiguo Li Hongbiao Dong Bingshe Xu Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024P.R.China Shanxi Key Laboratory of Advanced Magnesium-based Materials Taiyuan 030024P.R.China Department of Engineering University of LeicesterLeicester LE17RHUK

AZ61 Mg alloy with homogeneous refined microstructure and exceptional mechanical properties was obtained by the combined technology of equal-channel angular pressing(ECAP)and electropulsing treatment(EPT)in this *** on an ECAP die with an intersection angle of 160,the lower temperature is particularly adapted for AZ61 alloy to be deformed,in which accompanied by high accumulated defects *** recrystallization of EPTed samples during different stages indicated that the recrystallization behavior of the deformed Mg alloy was mainly affected by the processing time and duration of *** to those of the as-received samples,the average grain size of the EPTed samples was refined from 89μm to 1.0μm,accordingly the yields stress(YS)and ultimate tensile strength(UTS)were increased from 100 MPa and 260 MPa to 330 MPa and 448 MPa,*** mechanisms of microstructure transformation and the reinforced mechanical properties were analyzed based on the strain of single ECAP,cumulative storage energy and the athermal effect of EPT.

关键词： AZ61 Mg alloy Equal channel angular pressing Electropulsing treatment Recrystallization Mechanical properties

Effect of yttrium,calcium and zirconium on ignition-proof principle and mechanical properties of magnesium alloys

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Journal of Rare Earths 2012年第1期30卷 74-78页

作者： fan jianfeng CHEN Zhiyuan YANG Weidong fanG Shuang XU Bingshe Key laboratory of Interface Science and Engineering in Advanced Materials Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024China Shanxi Research Center of Advanced Materials Science and Technology Taiyuan University of TechnologyTaiyuan 030024China College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China

Good ignition-proof principle and mechanical properties were realized in Mg-Y-Ca-Zr alloy *** adding Y and Ca elements,the ignition point of Mg-3.5Y-0.8Ca alloy was improved to over 1173 K,and the alloy could be melted in air without any *** ef-fect of Zr addition on the microstructures and mechanical properties of Mg-3.5Y-0.8Ca alloys were investigated,and Mg-3.5%Y-0.8%Ca-0.4%Zr alloy had good comprehensive properties with tensile strength of 190 MPa and elongation of 11%.Auger electron spectros-copy（AES） and X-ray diffraction（XRD） analysis revealed that the oxide film formed on the surface of Mg-3.5Y-0.8Ca alloy was mainly composed of *** measurements in dry air indicated that the oxidation dynamics curves measured at 773,873 and 973 K followed the cubic ***,the semiconductor characteristic of Y2O3 film and its effect on ignition-proof properties of Magnesium al-loys were discussed from the viewpoint of electrochemistry.

关键词： magnesium alloys ignition proof principle mechanical properties rare earths