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50-110 GHz,high isolation,and high-power linearity single-pole double-throw switch utilizing 100-nm GaN HEMT technology

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The Journal of China Universities of Posts and Telecommunications 2024年第2期31卷 38-43,71页

作者： Han Qunfei Hu sanming Zhang Tianyu Chen Qing Shen Yizhu Wang Weibo Tao Hongqi School of Information Science and Engineering Southeast UniversityNanjing 210096China Nanjing Electronic Devices Institute Nanjing 210016China State Key Laboratory of Millimeter Waves Southeast UniversityNanjing 210096China

This article presents the design and performance of a single-pole double-throw(SPDT)switch operating in 50-110 *** switch is fabricated in a 100-nm GaN high-electron-mobility transistors(HEMT)*** realize high-power capability,the dimensions of GaN HEMTs are selected by simulation *** enhance the isolation,an improved structure of shunt HEMT with two ground holes is *** extend the operation bandwidth,the SPDT switch with multi-section resonant units is proposed and *** verify the SPDT switch design,a prototype operating in 50-110 GHz is *** measured results show that the fabricated SPDT switch monolithic microwave integrated circuit(MMIC)achieves an input 1 dB compression point(P_(1dB))of 38 dBm at 94 GHz,and isolation within the range of 33 dB to 54 dB in 50-110 *** insertion loss of the switch is less than 2.1 dB,while the voltage standing wave ratios(VSWR)of the input port and output port are both less than 1.8 in the operation *** on the measured results,the presented SPDT switch MMIC demonstrates high power capability and high isolation compared with other reported millimeter-wave SPDT MMIC designs.

关键词： GaN high-electron-mobility transistors(HEMT) millimeter-wave single-pole double-throw(SPDT) switch

A NOVEL INORGANIC MATERIAL FOR LIQUID LASER

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A NOVEL INORGANIC MATERIAL FOR LIQUID LASER

TiB_(2)含量对TiB_(x)/Ti合金涂层组织及摩擦学性能的影响

Asia Conference on Nanoscience and Nanotechnology Abstracts Book

作者： Zhongcheng FAN Rongbiao YU Xiaoming QIU Kehan YU Xiangxing XU Lei JIANG sanming si Dan CHEN Li XU Lei ZHAO Bo PENG Wei HUANGInstitute of Advanced Materials Fudan University Shanghai 200433 China.

＜正＞ Solid state lasers have been widely used in defense works, mechanical processing, information technology and many other areas. However, they still have quite a few disadvantages. As is well known, it is costly and difficult to homogeneously manufacture the crystal and glass bulks in big size. These solid bulks can not avoid defects, which will develop damaged spots when running before the spots grow rapidly. The growing spots are very harmful and even dangerous for the performance and maintenance of high power laser systems. What is more, it is awfully difficult to cool the solid lasing materials, thus the running cycle period and working life shrank badly, and the laser system become low repeated usable. Fortunately, inorganic liquid laser can gracefully tackle such nuts. First of all, it is pretty easy to get lasing liquid in almost unlimited volume at a uniform density. As far as most thin liquids are concerned, the structure is nearly ideally homogenized when flowing. Even if some defects are developed while lasing, the spots will get resolved by the flowing ambient branches to prevent such damage. It is also quite convenient to realize the high repeated laser to prolong both the running cycle period and working life. In our work, neodymium doped yttrium aluminum garnet （Nd: YAG） was manufactured through the aqueous solutions of aluminum, yttrium and neodymium chlorides. After calcination and sinter, Nd: YAG nanocrystals by the size of tens of nanometers were realized. They were homogeneously dispersed in inorganic solvent, such as POCl3, BBr3 and TiCl4, with properly adjusted refractive index and density. Tbe laser emission was also achieved while the mixture was recirculated. It might have a potential application in high repeated laser system.

关键词： liquid laser inorganic nanosized particle.

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表面技术 2024年第11期53卷 140-149页

作者：寇斐凡岳赟杜志浩杜三明陈德强张永振高端轴承摩擦学技术与应用国家地方联合工程实验室河南洛阳471023 河南科技大学材料科学与工程学院河南洛阳471023

目的在Ti-47Zr-5Al-3V(以下简称T47Z)表面制备TiB_(x)/Ti合金复合涂层,以提高合金的摩擦学性能。方法采用等离子弧熔覆技术在T47Z合金表面熔覆不同配比的(TiB_(2)+Ti)粉末,制备TiB_(x)陶瓷相增强钛合金复合涂层,使用扫描电镜(SEM)、X射... 详细信息

目的在Ti-47Zr-5Al-3V(以下简称T47Z)表面制备TiB_(x)/Ti合金复合涂层,以提高合金的摩擦学性能。方法采用等离子弧熔覆技术在T47Z合金表面熔覆不同配比的(TiB_(2)+Ti)粉末,制备TiB_(x)陶瓷相增强钛合金复合涂层,使用扫描电镜(SEM)、X射线衍射仪(XRD)、维氏硬度显微计和UMT-2摩擦磨损试验机对涂层微观组织、硬度及摩擦磨损性能进行测试研究。结果涂层厚度约2 mm,无裂纹、气孔等缺陷,涂层的基体组织为α相,针状、棒状的TiB增强相和颗粒状的TiB_(2)增强相均匀分布于α相中。随着TiB_(2)含量的增加,涂层基体组织无明显变化,增强相的数量增加,尺寸逐渐变大。涂层的表面硬度最高可达893.4HV0.2,约为基体的2.07倍。涂层的耐磨性相较基体均获得不同程度的提升,当TiB_(2)的质量分数为40%时,涂层的耐磨性提升最为显著,相较基体提高了53.7%。T47Z合金的磨损机理为严重的黏着磨损和磨粒磨损。TiB_(2)的质量分数为10%的涂层,其磨损机理以黏着磨损为主,磨粒磨损为辅。随着TiB_(2)含量的增加,涂层的磨损机制逐渐转向磨粒磨损。结论通过控制粉体中TiB_(2)的含量,能够利用等离子弧熔覆技术在钛合金表面制备TiB_(x)/Ti合金复合涂层,尤其当TiB_(2)的质量分数为40%时,涂层的硬度及耐磨性能均获得大幅度提升。因此,运用等离子熔覆技术制备陶瓷相增强金属基复合涂层可切实有效地提高钛合金的硬度及耐磨性能。

关键词：钛合金等离子弧熔覆显微组织涂层硬度摩擦磨损性能

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5G毫米波反向阵极简构架与CMOS芯片实现

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电子与信息学报 2024年第5期46卷 1570-1581页

作者：郭嘉诚胡三明沈一竹钱昀胡楚悠黄永明尤肖虎东南大学信息科学与工程学院南京210096 紫金山实验室南京211111

该文首次报道了一种极简构架的5G毫米波反向阵设计原理及其CMOS芯片实现技术。该毫米波反向阵极简构架,利用次谐波混频器提供相位共轭和阵列反向功能,无需移相电路及波束控制系统,便可实现波束自动回溯移动通信功能。该文采用国产0.18μ... 详细信息

该文首次报道了一种极简构架的5G毫米波反向阵设计原理及其CMOS芯片实现技术。该毫米波反向阵极简构架,利用次谐波混频器提供相位共轭和阵列反向功能,无需移相电路及波束控制系统,便可实现波束自动回溯移动通信功能。该文采用国产0.18μm CMOS工艺研制了5G毫米波反向阵芯片,包括发射前端、接收前端及跟踪锁相环等核心模块,其中发射及接收前端芯片采用次谐波混频及跨导增强等技术,分别实现了19.5 d B和18.7 d B的实测转换增益。所实现的跟踪锁相环芯片具备双模工作优势,可根据不同参考信号支持幅度调制及相位调制,实测输出信号相噪优于–125 dBc/Hz@100 kHz。该文给出的测试结果验证了所提5G毫米波反向阵通信架构及其CMOS芯片实现的可行性,从而为5G/6G毫米波通信探索了一种架构极简、成本极低、拓展性强的新方案。

关键词：毫米波集成电路 CMOS 反向阵射频前端

GCr15siMo钢中贝氏体含量对力学性能及干摩擦磨损性能的影响

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表面技术 2024年第7期53卷 48-56页

作者：毛艳珊杜三明傅丽华张永振高元安杨军魏超凡付壁聪河南科技大学高端轴承摩擦学技术与应用国家地方联合工程实验室河南洛阳471023 洛阳轴承研究所股份有限公司河南洛阳471003 中国科学院兰州化学物理研究所兰州730099

目的通过控制等温淬火时间,在GCr15siMo轴承钢中获得不同含量的贝氏体组织,并研究不同含量的贝氏体组织对材料力学性能和干摩擦磨损性能的影响。方法采用SEM、3D morphology、TEM、EDS、XRD、洛氏硬度计、冲击试验机等仪器观测GCr15siM... 详细信息

目的通过控制等温淬火时间,在GCr15siMo轴承钢中获得不同含量的贝氏体组织,并研究不同含量的贝氏体组织对材料力学性能和干摩擦磨损性能的影响。方法采用SEM、3D morphology、TEM、EDS、XRD、洛氏硬度计、冲击试验机等仪器观测GCr15siMo轴承钢经不同等温淬火时间后的微观组织、物相含量和力学性能,并使用HL-R7000重载往复摩擦磨损试验机对不同贝氏体组织含量的试样进行摩擦磨损性能检测。结果当等温淬火时间由2 h延长至72 h时,材料中贝氏体的体积分数由14.5%增至83.5%。随着GCr15siMo轴承钢材料中韧性贝氏体含量的增多、脆性马氏体含量的减少,其硬度逐渐降低,冲击功逐渐增大,磨损率呈现先降低再升高的趋势。材料的磨损机制主要为黏着磨损和磨粒磨损,随着等温淬火时间的延长,基于韧性贝氏体含量的增加,材料的磨粒磨损减弱、黏着磨损增强。结论在等温淬火温度为210℃、等温淬火时间为8 h时,材料中贝氏体的体积分数约为55.6%,马氏体的体积分数为33.2%,此时马氏体和贝氏体复相组织具有良好的强韧性匹配,材料的耐磨性能较好。

关键词：等温淬火工艺贝氏体力学性能摩擦磨损

囊胚活检中透明带开孔时机对临床结局影响的系统评价

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中华生殖与避孕杂志 2024年第5期44卷 488-492页

作者：桑元坤张丽媛王琰谢广妹史莉柴三明甘肃省妇幼保健院、甘肃省中心医院生殖医学中心兰州730070

目的系统比较滋养外胚层活检技术中同步透明带开孔与提前开孔的临床效果,为建立标准囊胚活检程序提供循证医学证据。方法计算机检索PubMed、Cochrane Library、Embase、Web of Science、中国生物医学文献数据库、中国期刊全文数据库、... 详细信息

目的系统比较滋养外胚层活检技术中同步透明带开孔与提前开孔的临床效果,为建立标准囊胚活检程序提供循证医学证据。方法计算机检索PubMed、Cochrane Library、Embase、Web of Science、中国生物医学文献数据库、中国期刊全文数据库、维普中文科技期刊数据库和万方数据库,检索时限均为建库至2023年8月。检索两种透明带开孔时机应用效果比较的研究文献,主要评价指标为临床妊娠率和活产率,次要评价指标包括活检成功率、整倍体囊胚率和流产率。采用R4.2.2软件meta程序包进行meta分析。结果共纳入6篇原始研究,包括12223枚活检胚胎,2374个移植周期。meta分析结果显示,同步开孔组的临床妊娠率(RR=1.22,95%CI:1.14~1.30,P<0.01)和活产率(RR=1.22,95%CI:1.12~1.32,P<0.01)均高于提前开孔组。两组间的活检成功率(RR=1.38,95%CI:0.30~6.25,P=0.68)、整倍体囊胚率(RR=0.98,95%CI:0.83~1.15,P=0.81)和流产率(RR=1.06,95%CI:0.77~1.47,P=0.73)差异均无统计学意义。结论同步透明带开孔囊胚活检方案在临床妊娠率和活产率方面优于提前开孔,受纳入研究样本量及质量的限制,透明带开孔时机对临床效果的影响还需更多高质量的研究。

关键词： Meta分析透明带开孔时机囊胚活检

不同载荷下轴承波纹状损伤的形成规律和材料损伤机制

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轴承 2024年第10期 39-45页

作者：娄志浩宋晨飞任雨龙杜三明张永振河南科技大学高端轴承摩擦学技术与应用国家地方联合工程实验室河南洛阳471023

轴承波纹状损伤是新能源汽车、风电、高速铁路中电气设施的常见故障。为揭示不同载荷下轴承电蚀的损伤形式和微观损伤机制,重点讨论了波纹状损伤亮区与暗区的差异,使用扫描电子显微镜、光学显微镜、三维轮廓仪、能谱仪检测磨损表面的形... 详细信息

轴承波纹状损伤是新能源汽车、风电、高速铁路中电气设施的常见故障。为揭示不同载荷下轴承电蚀的损伤形式和微观损伤机制,重点讨论了波纹状损伤亮区与暗区的差异,使用扫描电子显微镜、光学显微镜、三维轮廓仪、能谱仪检测磨损表面的形貌和成分。结果表明,随着载荷的增加,GCr15轴承外沟道表面亮暗相间的波纹状损伤趋于不明显,波纹的宽度、高度差和表面粗糙度Ra值均减小;相比于亮区,暗区电蚀更严重,氧化程度更低,次表层碳化物聚集更多且硬度更低。分析认为轴承波纹状损伤过程伴随着金属-绝缘膜-金属电容式接触的周期性破坏和重建。

关键词：滚动轴承外圈电蚀磨损载荷显微形貌分析硬度

Association between the physical stability of flurbiprofen suspension and the interaction of HPMC/SDS

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Asian Journal of Pharmaceutical Sciences 2018年第1期13卷 63-71页

作者： Hongyu Wang Yiwei Sun Baixue Yang sanming Li Shenyang Pharmaceutical University Linyi University

The anionic surfactant sodium dodecylsulfate(SDS) has improved the physical stability of flurbiprofen(FBP) suspension, which was suspended by 0.2%(w/v) hydroxypropylmethyl cellulose(HPMC, K4 M). Therefore, the physical stability of FBP suspensions and the interaction of HPMC/SDS were studied, and a certain association between them was revealed. The antisolvent precipitation method was used to prepare suspensions. The apparent drug concentration from different sites was evaluated to get the dispersion of drug actually. The process of flocculation and deflocculation with the addition of SDS was caught by analyzing the morphology of the suspended particles. The physical stability of the FBP suspensions was characterized mainly by measuring the re-dispersion time, the zeta potential and particle size. Meanwhile, conductivity measurements were carried out to obtain the characteristic concentrations of SDS in HPMC/SDS system. The viscosities, the abilities for improving the solubility and wettability of FBP in the separate and mixed HPMC/SDS solutions were also contrasted respectively. The suspensions prepared with HPMC/SDS possessed better physical stability. The suspensions were uniform when the concentration of SDS was between the critical adsorption concentration(CAC) and the polymer saturation point(PSP). After PSP, the uniformity became worse and worse until the SDS was enough to form a deflocculation state. Besides, the re-dispersion time of FBP suspensions was longest when the concentration of SDS around CAC and shorter by shorter after the critical micelle concentration(CMC). The article provided a new sight on the relation between the interaction of excipient matrix and pharmaceutical preparations.

关键词： Suspension stability HPMC/SDS Electrical conductivity Viscosity Solubilization Wettability

Effect of slope inclination on step friction coefficient of human being

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Science China(Technological Sciences) 2013年第12期56卷 3001-3006页

作者： ZHANG YongZhen JIA LiXiao PANG XianJuan NIU YongPing DU sanming Henan Key Laboratory of Material Tribology Henan University of Science & Technology Department of Mechanical & Electrical Engineering Luoyang Institute of Science and Technology

Effect of slope inclination on step friction coefficient of human being was studied by gait friction tester developed by Henan University of Science and *** is beneficial to improving the safety of human beings while walking on a *** on the trajectory of mass center of body(MCOB)and the mechanical analysis of human body while walking,conclusion could be drawn that the required step frictional coefficient(RSFC)exhibited an"M"shaped curve during the foot contacting with the ground and got its maximum and minimum values when MCOB of the subject was at the highest and lowest position ***,the first peak of RSFC decreases firstly and then increases,while the second peak of RSFC increases with the increase of slope inclination at the experimental *** position of pivotal point is decided by the relative size of slope inclination and the angle between the plumb line through MCOB and the line from foot to MCOB.

关键词： slope inclination step friction coefficient trajectory of mass center of body gait friction tester