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Interfacial microstructure evolution and bonding mechanisms of 14YWT alloys produced by hot compression bonding

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Journal of Materials Science & Technology 2019年第8期35卷 1671-1680页

作者： Liying Zhou shaobo feng Mingyue Sun Bin Xu Dianzhong Li Shenyang National Lab. for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China School of Materials Science and Engineering University of Science and Technology of China Shenyang 110016 China

Hot compression bonding was first used to join oxide-dispersion-strengthened ferrite steels(14 YWT)under temperatures of 750–1100℃ with a true strain range of 0.11–0.51. Subsequently, the microstructure evolution and mechanical properties of the joints were characterized, revealing that the 14 YWT steels could be successfully bonded at a temperature of at least 950℃ with a true strain of 0.22, without degrading the fine grain and nanoparticle distribution, and the presence of inclusions or micro-voids along the bonding interface. Moreover, the joints had nearly the same tensile properties at room temperature and exhibited a similar fracture morphology with sufficient dimples compared to that of the base material. An electron backscattered diffraction technique and transmission electron microscopy were systematically employed to study the evolution of hot deformed microstructures. The results showed that continuous dynamic recrystallization characterized by progressive subgrain rotation occurred in this alloy, but discontinuous dynamic recrystallization characterized by strain-induced grain boundary bulging and subsequent bridging sub-boundary rotation was the dominant nucleation mechanism. The nuclei will grow with ongoing deformation, which will contribute to the healing of the original bonding interface.

关键词： Oxide dispersion strengthened steels Hot compression bonding Dynamic recrystallization Tensile property

11.2 W/mm power density AlGaN/GaN high electron-mobility transistors on a GaN substrate

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Journal of Semiconductors 2024年第1期45卷 38-41页

作者： Yansheng Hu Yuangang Wang Wei Wang Yuanjie Lv Hongyu Guo Zhirong Zhang Hao Yu Xubo Song Xingye zhou Tingting Han shaobo Dun Hongyu Liu Aimin Bu Zhihong feng National Key Laboratory of Solid-State Microwave Devices and Circuits Hebei Semiconductor Research InstituteShijiazhuang 050051China

In this letter,high power density AlGaN/GaN high electron-mobility transistors(HEMTs)on a freestanding GaN substrate are reported.An asymmetricΓ-shaped 500-nm gate with a field plate of 650 nm is introduced to improve microwave power performance.The breakdown voltage(BV)is increased to more than 200 V for the fabricated device with gate-to-source and gate-to-drain distances of 1.08 and 2.92μm.A record continuous-wave power density of 11.2 W/mm@10 GHz is realized with a drain bias of 70 V.The maximum oscillation frequency(f_(max))and unity current gain cut-off frequency(f_(t))of the AlGaN/GaN HEMTs exceed 30 and 20 GHz,respectively.The results demonstrate the potential of AlGaN/GaN HEMTs on freestanding GaN substrates for microwave power applications.

关键词： freestanding GaN substrates AlGaN/GaN HEMTs continuous-wave power density breakdown voltage Γ-shaped gate

Dynamic recrystallization behavior and interfacial bonding mechanism of 14Cr ferrite steel during hot deformation bonding

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Journal of Materials Science & Technology 2020年第8期36卷 92-103页

作者： Liying Zhou Wenxiong Chen shaobo feng Mingyue Sun Bin Xu Dianzhong Li Shenyang National Lab.for Materials Science Institute of Metal ResearchChinese Academy of ScienceShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

In this study, hot compression bonding was first applied to join 14Cr ferrite steel at temperatures of 950–1200°C and strains of 0.11–0.51 under strain rates of 0.01–30 s^(-1).Subsequently, tensile tests were performed on the joints to evaluate the reliability of the joints formed.Detailed microstructural analyses suggest that two different competing dynamic recrystallization(DRX) mechanisms occur during the bonding process depending on the strain rate, and the joints obtained at different strain rate exhibits distinct healing effect.At a low strain rate(0.01 s^(-1)), continuous DRX occurs, as expected in high-stackingfault-energy materials, and is characterized by the progressive conversion of the sub-boundaries into larger-angle boundaries, which involves very limited grain boundaries migration.In addition, straininduced precipitation(SIP) is sufficient under this condition, further impeding the healing of bonding interface.Hence, the joints obtained at low strain rate fractured at the bonding interface easily.Whereas discontinuous DRX is activated at high strain rates(10 and 30 s^(-1)).Under this condition, the formation of sub-boundaries is severely suppressed, resulting in the piling-up of dislocations and hence the storage of a greater amount of stored energy for nucleation and subsequent nuclei growth via the long-distance grain boundaries migration.Meanwhile, the SIP process is sluggish, making the conditions much more favorable for grain boundaries migration which plays a key role in the healing of the original bonding interface.Thus, the joints can be successfully bonded when a high strain rate is applied, with the joints exhibiting tensile properties similar to that of the base material.

关键词： Hot compression bonding Dynamic recrystallization Ferrite Strain-induced precipitation Tensile property

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深地塔科1井钻井设计关键技术

石油钻探技术 2024年第2期52卷 78-86页

作者：王春生冯少波张志周波吕晓钢周宝中国石油超深层复杂油气藏勘探开发技术研发中心新疆库尔勒841000 新疆维吾尔自治区超深层复杂油气藏勘探开发工程研究中心新疆库尔勒841000 新疆超深油气重点实验室新疆库尔勒841000

深地塔科1井设计井深11100 m,预测井底温度213℃,预测地层压力133 MPa,钻井作业面临超深、超高温、超高压、高含硫“三超一高”的极端恶劣井况。通过开展地质工程一体化研究,确定了火成岩、膏盐岩及碳酸盐岩内裂缝的分布规律及其所带来... 详细信息

深地塔科1井设计井深11100 m,预测井底温度213℃,预测地层压力133 MPa,钻井作业面临超深、超高温、超高压、高含硫“三超一高”的极端恶劣井况。通过开展地质工程一体化研究,确定了火成岩、膏盐岩及碳酸盐岩内裂缝的分布规律及其所带来的工程风险,在实现地质目标的前提下进行了井位优化,以降低工程施工难度。在地质工程一体化研究和五压力剖面预测的基础上,充分考虑深部地层地质、工程风险,设计了五开井身结构;开展了超深井套管设计及校核,除考虑套管抗拉强度、钻机承载力外,模拟计算了井口工具对超长超重套管的作用力,避免了套管下入过程中发生塑性变形;钻具组合设计时,充分考虑了水力学参数及振动的影响,在最优钻井参数范围内实现安全钻进和提速。现场施工进展表明,深地塔科1井钻井设计关键技术能够解决面临的系列钻井技术难点,实现万米钻探工程目标。

关键词：深地塔科1井地质工程一体化井身结构超深井套管设计钻具设计

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库车山前气体钻井技术应用效果评价

钻采工艺 2024年第1期47卷 45-52页

作者：胥志雄冯少波范玉光张权李宁陈凯枫颜辉赵云中国石油塔里木油田公司新疆维吾尔自治区841000

塔里木油田从2006年来在库车山前大北、博孜、迪北3个区块开展了气体钻井技术的探索与应用,取得了显著效果。其中,针对塔里木库车山前高陡巨厚砾岩层研磨性强、可钻相差、井壁稳定性差等,开展了空气钻井技术的探索、升级配套以及优化完... 详细信息

塔里木油田从2006年来在库车山前大北、博孜、迪北3个区块开展了气体钻井技术的探索与应用,取得了显著效果。其中,针对塔里木库车山前高陡巨厚砾岩层研磨性强、可钻相差、井壁稳定性差等,开展了空气钻井技术的探索、升级配套以及优化完善,有效解决了库车山前砾石核心区地层难钻的问题,大幅提高了钻井效率,新实施井平均机械钻速达到6.93 m/h,是同区钻井液钻进的两倍以上,钻井周期较设计缩短54.2%;针对迪北构造阿合组致密敏感性储层采用氮气钻完井技术,“零污染”钻进,扩大了勘探发现,提高了开发产能,DB104井日产气量高达72.6×104m3,日产油量51.36 m3,与同区块常规钻完井方式相比,大幅度提高了日产气量。但气体钻完井中仍然存在油钻杆完井管柱不能满足长效安全生产等问题,建议持续开展技术攻关,以保障氮气钻安全钻进和开发。通过文章的梳理,有助于塔里木油田气体钻井技术进一步发展,同时为国内其他区块的气体钻井技术升级提供借鉴。

关键词：库车山前致密砂岩气藏阿合组储层气体钻井提速提效储层保护

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单发纯磨玻璃结节为表现的肺转移癌一例

中国胸心血管外科临床杂志 2024年第3期31卷 485-488页

作者：敬涛宋铁牛魏小平冯海明张少博王成蒋鹏李斌兰州大学第二医院胸外科兰州730000

报道1例乳腺癌肺转移32岁女性患者,以单发纯磨玻璃结节(ground-glass opacity,GGO)病变为表现。虽然术前诊断不准确,但患者接受了合理的术前检查和手术治疗。由于不同的治疗策略和目的,区分非典型转移瘤与原发癌是至关重要的。因此,如果... 详细信息

报道1例乳腺癌肺转移32岁女性患者,以单发纯磨玻璃结节(ground-glass opacity,GGO)病变为表现。虽然术前诊断不准确,但患者接受了合理的术前检查和手术治疗。由于不同的治疗策略和目的,区分非典型转移瘤与原发癌是至关重要的。因此,如果在CT上发现新的GGO,有恶性肿瘤史的患者应考虑有转移可能性。此外,应适当缩短CT随访间隔,根据多学科团队建议进行术前检查和手术治疗。

关键词：乳腺癌肺转移瘤纯磨玻璃结节手术病例报告

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集成电路用电子特气合成与纯化技术研究进展

化学工程 2024年第5期52卷 46-52,78页

作者：孟祥军花莹曦冯昭宇郑凯天尚青姚冰洁李茹霞李绍波许春建天津大学化工学院化学工程联合国家重点实验室天津300072 中船(邯郸)派瑞特种气体股份有限公司河北邯郸056002

电子特气在集成电路制造过程的多个关键工艺步骤中发挥着重要作用。为确保最终的集成电路产品具备良好的电性指标及良品率,要求电子特气具有很高的产品纯度和严苛的质量一致性。然而,电子气体种类繁多,关键杂质种类及含量标准各不相同,... 详细信息

电子特气在集成电路制造过程的多个关键工艺步骤中发挥着重要作用。为确保最终的集成电路产品具备良好的电性指标及良品率,要求电子特气具有很高的产品纯度和严苛的质量一致性。然而,电子气体种类繁多,关键杂质种类及含量标准各不相同,因此各种电子特气的合成及纯化手段存在较大差异。文中重点关注市场需求量大的三氟化氮、六氟化钨和六氟丁二烯等产品,系统总结在电子特气合成与纯化过程中相关合成与纯化技术的研究进展及共性技术问题,以期为集成电路制造用电子特气的行业发展与技术进步提供参考和借鉴。

关键词：集成电路气体电解合成分离纯化

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粤北地区无花果水肥一体化设施栽培技术规程

现代农业科技 2024年第5期 217-220页

作者：冯慧敏何少波肖远业李海渤韶关学院生物与农业学院广东韶关512005 乐昌市水牛湾农业发展有限公司广东乐昌512200

设施栽培是指利用温室、塑料大棚或其他设施,通过改变或控制农作物生长发育的环境因子(光照、温度、水分、二氧化碳等)对农作物生产进行调控的一项新技术。目前关于广东省设施栽培无花果的报道相对较少,为规范设施无花果栽培技术,种植... 详细信息

设施栽培是指利用温室、塑料大棚或其他设施,通过改变或控制农作物生长发育的环境因子(光照、温度、水分、二氧化碳等)对农作物生产进行调控的一项新技术。目前关于广东省设施栽培无花果的报道相对较少,为规范设施无花果栽培技术,种植出高品质无花果,本文总结了粤北地区设施无花果栽培的产地环境、选址建棚、设施栽植、设施水肥管理、无花果整形修剪、病虫草害防治、收获和储藏等技术要点,以期为粤北地区无花果标准化种植提供依据。

关键词：无花果设施栽培水肥一体化技术规程粤北地区

Acellular nerve grafts supplemented with induced pluripotent stem cell-derived exosomes promote peripheral nerve reconstruction and motor function recovery

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Bioactive Materials 2022年第9期7卷 272-287页

作者： Jianfeng Pan Meng Zhao Xiangjiao Yi Jianguo Tao shaobo Li Zengxin Jiang Biao Cheng Hengfeng Yuan feng Zhang Department of Orthopedics Shanghai Tenth People’s HospitalSchool of MedicineTongji UniversityShanghai200072China Diseases&Population Geninfo Lab School of Life SciencesWestlake UniversityHangzhouZhejiang310024China Institute of Orthopaedics and Traumatology Zhejiang Chinese Medical University Affiliated First Affiliated HospitalHangzhouZhejiang310024China Department of Orthopaedics Shanghai Jiaotong University Affiliated Sixth People’s HospitalShanghai200233China Institute of Microsurgery On Extremities Shanghai Jiao Tong University Affiliated Sixth People’s HospitalShanghai200233China Joseph M.Still Burn and Reconstructive Center JacksonMS39204USA

Peripheral nerve injury is a great challenge in clinical work due to the restricted repair gap and weak regrowth ability.Herein,we selected induced pluripotent stem cells(iPSCs)derived exosomes to supplement acellular nerve grafts(ANGs)with the aim of restoring long-distance peripheral nerve defects.Human fibroblasts were reprogrammed into iPSCs through non-integrating transduction of Oct3/4,Sox2,Klf4,and c-Myc.The obtained iPSCs had highly active alkaline phosphatase expression and expressed Oct4,SSEA4,Nanog,Sox2,which also differentiated into all three germ layers in vivo and differentiated into mature peripheral neurons and Schwann cells(SCs)in vitro.After isolation and biological characteristics of iPSCs-derived exosomes,we found that numerous PKH26-labeled exosomes were internalized inside SCs through endocytotic pathway and exhibited a proliferative effect on SCs that were involved in the process of axonal regeneration and remyelination.After that,we prepared ANGs via optimized chemical extracted process to bridge 15 mm long-distance peripheral nerve gaps in rats.Owing to the promotion of iPSCs-derived exosomes,satisfactory regenerative outcomes were achieved including gait behavior analysis,electrophysiological assessment,and morphological analysis of regenerated nerves.Especially,motor function was restored with comparable to those achieved with nerve autografts and there were no significant differences in the fiber diameter and area of reinnervated muscle fibers.Taken together,our combined use of iPSCs-derived exosomes with ANGs demonstrates good promise to restore long-distance peripheral nerve defects,and thus represents a cell-free strategy for future clinical applications.

关键词： Induced pluripotent stem cells Exosomes Acellular nerve grafts Peripheral nerve reconstruction Motor function recovery