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Modulation of phase boundary and domain structures to engineer strain properties in BNT-based ferroelectrics

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Journal of Advanced Ceramics 2024年第7期13卷 967-975页

作者： Yule Yang Zhiyong Liu Pengrong ren Yuqing Mao haijun Sun Bingliang Liang Pu Mao Kun Guo Bing Xie Longlong Shu School of Materials Science and Engineering Nanchang Hangkong UniversityNanchang 330063China School of Materials Science and Engineering Xi'an University of TechnologyXi’an 710048China School of Aircraft Engineering Nanchang Hangkong UniversityNanchang 330063China School of Physics and Materials Science Nanchang UniversityNanchang 330031China

Bismuth sodium titanate(BNT)ceramics exhibit outstanding strain responses but are unfavorable for application in high-sensitivity displacement actuators due to the large negative strain resulting from irreversible changes in their phase transition and domain ***,(1−x)Bi_(0.50)Na_(0.41)K_(0.09)TiO_(3)-xNaNbO_(3)(BNKT−xNN)solid solutions were prepared to improve the strain properties through the strategy of modulating the phase boundary and domain *** introduction of sodium niobate could effectively regulate the relative content of the tetragonal(P4bm)and rhombohedral(R3c)phases in the phase boundary *** ferroelectric-to-relaxor phase transition(T_(F−R))was reduced,and the ergodic relaxor(ER)state was nurtured at room *** zero-negative strain properties of S=0.41%and d_(33)^(*)=742 pm/V were achieved from the reversible transition between the ER and ferroelectric states under an applied electric field(x=0.04).Additionally,understanding the domain states via piezoelectric force microscopy(PFM)and firstorder reversal curve(FORC)revealed that the superior strain responses originated from the reversible inter-transformation of substable macrodomains and polar nanoregions(PNRs)in the phase *** study provides new insight into the interplay between the evolution of phase boundaries and domain structures and the strain properties of BNT-based ceramics.

关键词： bismuth sodium titanate(BNT) domain structure phase boundary strain response relaxor state

Distribution control and formation mechanism of gas inclusions in directionally solidified Al2O3-Er3Al5O12-ZrO2 ternary eutectic ceramic by laser floating zone melting

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Journal of Materials Science & Technology 2021年第7期66卷 21-27页

作者： haijun Su Yuan Liu Qun ren Zhonglin Shen Haifang Liu Di Zhao Guangrao Fan Min Guo Jun Zhang Lin Liu Hengzhi Fu Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen518057China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an710072China

Distribution control and formation mechanism of gas inclusions formed in directionally solidified Al2O3-Er3Al5O12-ZrO2 eutectic ceramic rods are explored during laser floating zone melting. In atmospheric environment, highly-dense bubble-free eutectic rods are well fabricated at low solidification rate(<25μm/s). Gas inclusions form intermittently when the solidification rate is in the range of 25-50 μm/s,but produce continuously at higher solidification rates(100-200 μm/s). The gas inclusions exhibit an elongated finger-like pattern along the growth direction, which of the maximum value of diameter first increases and then decreases with increasing the solidification rate. Meanwhile, the volume fraction of gas inclusions increased gradually with the solidification rate. Based on the effect of surface tension gradient, heterogeneous nucleation of gas bubbles is evaluated to be the primary formation mechanism of gas inclusions.

关键词： Directional solidification Gas inclusions Eutectic oxide Laser floating zone melting Formation mechanism

螺旋CT三维血管成像在脑膜瘤外科治疗中的应用

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中华神经外科疾病研究杂志 2007年第5期6卷 447-449页

作者：王治民徐香玖陈天立潘亚文任海军张新定甘肃省人民医院放射科甘肃兰州730000 甘肃省人民医院神经外科甘肃兰州730000 兰州大学第二医院神经外科甘肃兰州730030

目的探讨螺旋CT三维血管成像(3D-CTA)对脑膜瘤及其周围组织的显示能力,评价其在外科治疗中的价值。方法脑膜瘤患者32例,所有病例均行CT平扫和增强扫描。图像送至AW工作站进行多平面重建(MPR)、最大密度投影(MIP)、容积再现(VR)、表面遮... 详细信息

目的探讨螺旋CT三维血管成像(3D-CTA)对脑膜瘤及其周围组织的显示能力,评价其在外科治疗中的价值。方法脑膜瘤患者32例,所有病例均行CT平扫和增强扫描。图像送至AW工作站进行多平面重建(MPR)、最大密度投影(MIP)、容积再现(VR)、表面遮蔽法(SSD)后处理观察。结果重建图像显示瘤体充分强化,颅骨、血管、肿瘤三者立体关系显示清楚,主要的征象包括血管被肿瘤包绕,颅骨受侵犯,肿瘤周围组织移位等。结论3D-CTA可以充分显示脑膜瘤的影像特征,使血管充分强化,重建后可清楚显示肿瘤、血管及其与邻近组织的关系,有助于脑膜瘤的诊断及治疗方案的制订,评估手术风险。

关键词：多层螺旋CT 血管造影脑膜瘤

经颅多普勒超声在重型颅脑创伤救治中的临床应用

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中华神经创伤外科电子杂志 2018年第6期4卷 374-376页

作者：李瑞豪任海军侯博儒杨文桢王登峰薛鑫卢维新兰州大学第二医院神经外科兰州730000

重型颅脑创伤(sTBI)的临床监测手段多以体格检查、影像学检查为主,而这些手段无法迅速有效地诊断、监测sTBI病理生理过程。经颅多普勒超声(TCD)可以无创、实时地测量大脑大动脉的血流状态,获得脑血流动力学信息,通过分析脑血流速度及方... 详细信息

重型颅脑创伤(sTBI)的临床监测手段多以体格检查、影像学检查为主,而这些手段无法迅速有效地诊断、监测sTBI病理生理过程。经颅多普勒超声(TCD)可以无创、实时地测量大脑大动脉的血流状态,获得脑血流动力学信息,通过分析脑血流速度及方向、血管自身调节功能、远端血管阻力变化来监测脑血管狭窄、痉挛程度并评估颅内压、识别脑死亡。本文围绕TCD在sTBI救治中的临床应用综述如下。

关键词：重型颅脑创伤经颅多普勒颅内压脑死亡

Biliary stents for active materials and surface modification:Recent advances and future perspectives

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Bioactive Materials 2024年第12期42卷 587-612页

作者： Yuechuan Li Kunshan Yuan Chengchen Deng Hui Tang Jinxuan Wang Xiaozhen Dai Bing Zhang Ziru Sun Guiying ren haijun Zhang Guixue Wang Key Laboratory for Biorheological Science and Technology of Ministry of Education National Local Joint Engineering Laboratory for Vascular ImplantsBioengineering College of Chongqing UniversityChongqing400044China Shanghai Tenth People’s Hospital School of MedicineTongji UniversityShanghai200092China National United Engineering Laboratory for Biomedical Material Modification Dezhou251100China School of Biosciences and Technology Chengdu Medical CollegeChengdu610500China Nanjing Key Laboratory for Cardiovascular Information and Health Engineering Medicine(CVIHEM) Drum Tower HospitalNanjing UniversityNanjingChina College of materials science and engineering Shandong University of TechnologyZibo25500ShandongChina

Demand for biliary stents has expanded with the increasing incidence of biliary *** implantation of plastic or self-expandable metal stents can be an effective treatment for biliary ***,these stents are nondegradable and prone to *** removal or replacement of the nondegradable stents is necessary in cases of disease resolution or *** overcome these shortcomings,improvements were made to the materials and surfaces used for the ***,this paper reviews the advantages and limitations of nondegradable ***,emphasis is placed on biodegradable polymer and biodegradable metal stents,along with functional *** also encompasses tissue engineering&3D-printed stents were ***,the future perspectives of biliary stents,including pro-epithelialization coatings,multifunctional coated stents,biodegradable shape memory stents,and 4D bioprinting,were discussed.

关键词： Biliary stent Biodegradable Functional coatings Tissue engineering&3D-printed stent Shape memory

Rational design of nanoarray structures for lithium-sulfur batteries:recent advances and future prospects

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Materials Futures 2023年第4期2卷 53-78页

作者： Longtao ren Jun Liu Abdul Hameed Pato Yan Wang Xiwen Lu Imran Ali Chandio Mingyue Zhou Wen Liu haijun Xu Xiaoming Sun College of Chemistry Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China State Key Laboratory of Chemical Resource Engineering Beijing 100029People’s Republic of China Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing 100029People’s Republic of China Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084People’s Republic of China College of Mathematics and Physics Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China

Lithium-sulfur(Li-S)batteries are considered as promising candidates for future-generation energy storage systems due to their prominent theoretical energy ***,their application is still hindered by several critical issues,e.g.,the low conductivity of sulfur species,the shuttling effects of soluble lithium polysulfides,volumetric expansion,sluggish redox kinetics,and uncontrollable Li dendritic *** research efforts have been devoted to breaking through the obstacles that are preventing Li-S batteries from realizing practical ***,benefiting from the no additives/binders,buffer of volume change,high sulfur loading and suppression of lithium dendrites,nanoarray(NA)structures have have emerged as efficient and durable electrodes in Li-S *** this work,recent advances in the design,synthesis and application of NA structures in Li-S batteries are ***,the multifunctional merits and typical synthetic strategies of employing NA structure electrodes for Li-S batteries are ***,the applications of NA structures in Li-S batteries are discussed ***,the challenge and rational design of NA structure for Li-S batteries are analyzed in depth,with the aim of providing promising orientations for the commercialization of high-energy-density Li-S batteries.

关键词： nanoarrays electrocatalysts surface and interface engineering lithium–sulfur batteries modulated strategies

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自励式缓速器的设计与试验研究

汽车工程 2010年第3期32卷 258-262页

作者：沈海军何仁杨效军江苏大学汽车与交通工程学院镇江212013

基于转筒式电涡流缓速器与永磁发电机功能相结合的思想,提出了一种自励式电涡流缓速器的方案,并设计和制造了制动转矩为500N.m的自励式缓速器样机。最后在台架上进行了自励式缓速器的制动转矩、转筒温度和1500r/min拖磨试验,揭示了自励... 详细信息

基于转筒式电涡流缓速器与永磁发电机功能相结合的思想,提出了一种自励式电涡流缓速器的方案,并设计和制造了制动转矩为500N.m的自励式缓速器样机。最后在台架上进行了自励式缓速器的制动转矩、转筒温度和1500r/min拖磨试验,揭示了自励式缓速器的某些特性。

关键词：车辆自励式缓速器设计试验

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区分车辆起讫信息的拥挤道路使用收费模型

系统工程理论与实践 2019年第5期39卷 1189-1197页

作者：任涛黄海军刘天亮北京航空航天大学经济管理学院北京100191

拥挤道路使用收费被视为缓解城市交通拥堵的有效手段之一.本文发展了一个区分车辆起讫点信息的路段收费模型,并将其与边际社会成本收费、一般路段收费和路径收费模型进行了严格比较.四种收费方式均能实现系统最优的路段流量分布,且收费... 详细信息

拥挤道路使用收费被视为缓解城市交通拥堵的有效手段之一.本文发展了一个区分车辆起讫点信息的路段收费模型,并将其与边际社会成本收费、一般路段收费和路径收费模型进行了严格比较.四种收费方式均能实现系统最优的路段流量分布,且收费收益只与OD需求及收费用户均衡时的最小路径费用相关.边际社会成本收费方式产生的网络总收费最高,一般路段收费方式次之,然后是本文提出的收费策略,路径收费方式产生的总收费最小.一般路段收费可匿名实施,路径收费需要获取出行者完整的路径信息,本文提出的收费策略只需获取出行者的起讫点信息.在一个多OD对交通网络上完成的数值计算验证了理论结果.

关键词：交通网络系统最优用户均衡拥挤收费

考虑桩土相互作用的“品”字型抗滑桩计算方法

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四川大学学报（工程科学版） 2015年第3期47卷 29-36页

作者：任永忠朱彦鹏李海军兰州理工大学甘肃省土木工程防灾减灾重点实验室甘肃兰州730050 兰州理工大学西部土木工程防灾减灾教育部工程研究中心甘肃兰州730050 甘肃省地矿局第三地质矿产勘查院甘肃兰州730050

基于对抗滑桩在滑坡防治工程中的应用研究,提出一种新型组合式"品"字型抗滑桩,抗滑桩由3根单桩通过桩顶连梁连接组成空间结构,具有刚度大、变形小的特点;基于位移土压力模型,建立桩身挠曲线微分方程,后排桩在滑坡推力作用下发生变形并... 详细信息

基于对抗滑桩在滑坡防治工程中的应用研究,提出一种新型组合式"品"字型抗滑桩,抗滑桩由3根单桩通过桩顶连梁连接组成空间结构,具有刚度大、变形小的特点;基于位移土压力模型,建立桩身挠曲线微分方程,后排桩在滑坡推力作用下发生变形并直接作用于桩间土上,引入Boussinesq解,通过对桩间土附加应力的求解进一步计算作用于前排桩的附加滑坡推力;将"品"字型抗滑桩应用于舟曲锁儿头滑坡,通过现场试验和现场监测与理论计算方法所得弯矩值和位移值的对比表明,所建立的计算方法合理可行,为进一步研究桩土相互作用的抗滑桩受力机理提供了一定的依据。

关键词：抗滑桩位移土压力桩身弯矩现场试验锁儿头滑坡