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High Voltage 2024年第1期9卷 46-55页

作者： Yan Yang Xueyang bai yuxing Lei Kai Liu Guangning Wu School of Electrical Engineering Southwest Jiaotong UniversityChengduChina

The lifetime model of turn-to-turn insulation in inverter-fed motors is studied.A lifetime model has been built by considering the effect of inverter-generated high voltage rise rate(dv/dt up to 20 V/ns).This model is followed by the generalised probabilistic model,in which the lifetime is proportional to the nth power of the voltage rise rate.Moreover,by investigating the effect of voltage rise rate on the partial discharge characteristics,it is found that the effect of voltage rise rate on the charge transport process in a voltage cycle is similar to that of the voltage amplitude.The enhanced partial discharge activity and induced charges are responsible for accelerated ageing and thus determine the final lifetime of turn-to-turn insulation.In this case,the generalised probabilistic electric lifetime model is applicable to the voltage rise rate as well as the voltage amplitude.

关键词： lifetime inverter insulation

Li^(+)doping induced zero-thermal quenching in Cs_(3)Zn_(6-x-y)B_(9)O_(21):xEu^(3+),yLi^(+)(0≤x≤0.10,0.06≤y≤0.16)

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Journal of Rare Earths 2023年第10期41卷 1478-1486,I0001页

作者： yuxing bai Liwei Wu Qilin Cheng Li Wu Yongfa Kong Yi Zhang Jingjun Xu Key Laboratory of Weak-Light Nonlinear Photonics Ministry of EducationSchool of PhysicsNankai UniversityTianjin300071China College of Science Civil Aviation University of ChinaTianjin300300China Institute of Photo-electronic Thin Film Devices and Technology Nankai UniversityTianjin300071China

Thermal stability is a crucial index to assess application value of high-power LEDs,which is related to lattice defects.Herein,an effective structure-engineering strategy is proposed to achieve excellent properties.Under the 394 nm excitation,Cs_3Zn_(5.94)B_9O_(21):0.06Eu^(3+)possesses two characteristic emissions peaked at 591 and 612 nm with limited thermal stability.By introducing Li^(+)ions into the lattice,the sample exhibits high color purity and excellent zero-thermal quenching because the defect contents of the phosphor can be effectively modulated via charge-compensation effect.Then,under the stimulus of high temperature,the corresponding trap levels with a suitable depth(E=1.27 eV)will release electrons to recombine with the luminescent centers,compensating for the energy loss.The study provides a meaningful guide for optimizing and designing novel functional photoluminescent materials.

关键词： Photoluminescence Charge compensation Lattice defects Thermal stability Rare earths

Biocompatible reduced graphene oxide stimulated BMSCs induce acceleration of bone remodeling and orthodontic tooth movement through promotion on osteoclastogenesis and angiogenesis

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Bioactive Materials 2022年第9期7卷 409-425页

作者： Delong Jiao Jing Wang Wenting Yu Ke Zhang Ning Zhang Lingyan Cao Xinquan Jiang yuxing bai Institute of Dental Research Beijing Stomatological Hospital&School of StomatologyCapital Medical UniversityBeijing100050China Department of Orthodontics Beijing Stomatological Hospital&School of StomatologyCapital Medical UniversityBeijing100050China Department of Prosthodontics Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineCollege of StomatologyShanghai Jiao Tong UniversityNational Center for StomatologyNational Clinical Research Center for Oral DiseasesShanghai Key Laboratory of StomatologyShanghai Engineering Research Center of Advanced Dental Technology and MaterialsShanghai200011China

We has synthesized the biocompatible gelatin reduced graphene oxide(GOG)in previous research,and in this study we would further evaluate its effects on bone remodeling in the aspects of osteoclastogenesis and angiogenesis so as to verify its impact on accelerating orthodontic tooth movement.The mouse orthodontic tooth movement(OTM)model tests in vivo showed that the tooth movement was accelerated in the GOG local injection group with more osteoclastic bone resorption and neovascularization compared with the PBS injection group.The analysis on the degradation of GOG in bone marrow stromal stem cells(BMSCs)illustrated its good biocompatibility in vitro and the accumulation of GOG in spleen after local injection of GOG around the teeth in OTM model in vivo also didn’t influence the survival and life of animals.The co-culture of BMSCs with hematopoietic stem cells(HSCs)or human umbilical vein endothelial cells(HUVECs)in transwell chamber systems were constructed to test the effects of GOG stimulated BMSCs on osteoclastogenesis and angiogenesis in vitro.With the GOG stimulated BMSCs co-culture in upper chamber of transwell,the HSCs in lower chamber manifested the enhanced osteoclastogenesis.Meanwhile,the co-culture of GOG stimulated BMSCs with HUVECs showed a promotive effect on the angiogenic ability of HUVECs.The mechanism analysis on the biofunctions of the GOG stimulated BMSCs illustrated the important regulatory effects of PERK pathway on osteoclastogenesis and angiogenesis.All the results showed the biosecurity of GOG and the biological functions of GOG stimulated BMSCs in accelerating bone remodeling and tooth movement.

关键词： Bone remodeling Reduced graphene oxide Angiogenesis Osteoclastogenesis Orthodontic tooth movement

Effects of water-aging for 6 months on the durability of a novel antimicrobial and protein-repellent dental bonding agent

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International Journal of Oral Science 2018年第3期10卷 160-167页

作者： Ning Zhang Ke Zhang Michael D.Weir David J.Xu Mark A.Reynolds yuxing bai Hockin H.K.Xu Department of Orthodontics School of StomatologyCapital Medical UniversityBeijingChina Biomatexrials&Tissue Engineering Division Department of EndodonticsPeriodontics and ProsthodonticsUniversity of Maryland Dental SchoolBaltimoreMDUSA Center for Stem Cell Biology&Regenerative Medicine University of Maryland School of MedicineBaltimoreMDUSA Marlene and Stewart Greenebaum Cancer Center University of Maryland School of MedicineBaltimoreMDUSA Department of Mechanical Engineering University of MarylandBaltimore CountyMDUSA

Biofilms at the tooth-restoration bonded interface can produce acids and cause recurrent caries. Recurrent caries is a primary reason for restoration failures. The objectives of this study were to synthesize a novel bioactive dental bonding agent containing dimethylaminohexadecyl methacrylate(DMAHDM) and 2-methacryloyloxyethyl phosphorylcholine(MPC) to inhibit biofilm formation at the tooth-restoration margin and to investigate the effects of water-aging for 6 months on the dentin bond strength and protein-repellent and antibacterial durability. A protein-repellent agent(MPC) and antibacterial agent(DMAHDM) were added to a Scotchbond multi-purpose(SBMP) primer and adhesive. Specimens were stored in water at 37 °C for 1, 30, 90, or 180 days(d).At the end of each time period, the dentin bond strength and protein-repellent and antibacterial properties were evaluated. Protein attachment onto resin specimens was measured by the micro-bicinchoninic acid approach. A dental plaque microcosm biofilm model was used to test the biofilm response. The SBMP + MPC + DMAHDM group showed no decline in dentin bond strength after water-aging for 6 months, which was significantly higher than that of the control(P 0.1). In conclusion, a bonding agent with MPC and DMAHDM achieved a durable dentin bond strength and long-term resistance to proteins and oral bacteria. The novel dental bonding agent is promising for applications in preventive and restorative dentistry to reduce biofilm formation at the tooth-restoration margin.

关键词： MPC Effects of water-aging for 6 months on the durability of a novel antimicrobial and protein-repellent dental bonding agent

四网融合条件下以客流需求为导向的市域铁路运输组织优化建议

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城市轨道交通研究 2024年第4期27卷 1-4页

作者：柏成刘裕行张炜晗朱炜滕靖同济大学交通运输工程学院上海201804 上海市轨道交通结构耐久与系统安全重点实验室上海201804

[目的]区域一体化建设对区域多层次轨道交通网络的融合发展提出了更高的要求。在四网融合趋势下,应充分考虑客流需求,以客流需求为导向进行市域铁路的运输组织优化。[方法]从长江三角洲等区域轨道交通四网融合背景和市域铁路在其中的功... 详细信息

[目的]区域一体化建设对区域多层次轨道交通网络的融合发展提出了更高的要求。在四网融合趋势下,应充分考虑客流需求,以客流需求为导向进行市域铁路的运输组织优化。[方法]从长江三角洲等区域轨道交通四网融合背景和市域铁路在其中的功能定位出发,明确了轨道交通互联互通的内涵。从客运需求总量、市域铁路客流分担率、运力供给和客运需求的匹配性3个方面阐述了当前市域铁路面临的运输组织困境。以客流需求为导向,从战略层、策略层及运营层3个层面提出了市域铁路运输组织的优化建议。[结果及结论]当前市域铁路运输组织的3大制约因素分别为线路规划建设与客运需求的差异、市域铁路与其他运输方式竞争优势不明显、缺少客流导向的列车开行方案调整机制及方法。从战略层角度应强化顶层设计,形成一体化运输组织体系;从策略层角度应化竞为合,发挥多模式轨道交通网络化效应;从运营层角度应以人为本,实行多样化行车组织模式。

关键词：市域铁路四网融合区域交通一体化客流需求导向运输组织优化

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密封沉积处理对纤维素纳米晶体薄膜光学特性的调控

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食品工业科技 2024年第4期45卷 1-9页

作者：白辰雨周宇星崔然然陈志彪梁栩鹏马涛宋弋中国农业大学食品科学与营养工程学院北京100083 国家果蔬加工工程技术研究中心北京100083 农业农村部果蔬加工重点实验室北京100083 广西青轻生物科技有限公司广西防城港538000

纤维素纳米晶体(Cellulose nanocrystal,CNC)在特定浓度下可自组装排列,赋予体系独特的光学性能。为阐明CNC薄膜形成过程中CNC自组装行为机制,本文通过分析CNC薄膜在宏观颜色、紫外可见光谱、偏振光学、微观形貌以及晶体结构等方面的变... 详细信息

纤维素纳米晶体(Cellulose nanocrystal,CNC)在特定浓度下可自组装排列,赋予体系独特的光学性能。为阐明CNC薄膜形成过程中CNC自组装行为机制,本文通过分析CNC薄膜在宏观颜色、紫外可见光谱、偏振光学、微观形貌以及晶体结构等方面的变化,探究了密封沉积时间和CNC浓度对自然蒸发干燥薄膜内部胆甾相液晶形成与排列的影响。结果表明,当密封沉积时间延长至48 h后,CNC薄膜的结构色显色范围、胆甾相结构的长程有序性均得到明显提升。随着浓度的升高,CNC颗粒间距减小,相邻颗粒间扭转角增大,螺距被压缩,从480 nm减小至344 nm。此外,密封沉积处理对高浓度CNC悬浮液形成长程有序性胆甾相结构具有明显优势。本研究结果表明,延长密封沉积时间和提高CNC浓度可以提高薄膜中长程有序性的提高,并促进胆甾相结构域的形成。这进一步完善了CNC基智能包装材料制备的科学基础,对于新型可视化食品包装和检测材料的开发具有积极作用。

关键词：纤维素纳米晶体薄膜密封沉积自组装胆甾相液晶

黄河流域(榆林段)畜禽养殖污染现状及防治对策研究

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现代畜牧科技 2024年第6期 112-114页

作者：张昕白文军武玉兴陕西省府谷县动物疫病预防控制中心陕西府谷719400

榆林区域畜禽养殖污染已成为该地区面临的严重环境问题。该文旨在对其现状进行全面评估,并提出有效的治理对策。通过对畜禽养殖规模、排放污染物种类和量化、污染对环境和人类健康的影响进行科学分析,深入剖析了污染问题的根源和危害程... 详细信息

榆林区域畜禽养殖污染已成为该地区面临的严重环境问题。该文旨在对其现状进行全面评估,并提出有效的治理对策。通过对畜禽养殖规模、排放污染物种类和量化、污染对环境和人类健康的影响进行科学分析,深入剖析了污染问题的根源和危害程度。针对现状,提出饲料改良、粪污资源化利用等技术手段,以及加强排污监管体系、推动畜禽养殖与农田一体化治理等综合对策。未来研究将侧重于技术创新、政策法规完善等方面,以实现畜禽养殖业的可持续发展和环境保护。通过该文的研究和对策提出,以期为榆林区域畜禽养殖污染问题的治理提供有效的科学支持,促进畜禽养殖业的可持续发展,实现经济、社会和环境的协调与可持续发展。

关键词：畜禽养殖污染防治对策

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Advanced smart biomaterials and constructs for hard tissue engineering and regeneration

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Bone Research 2018年第4期6卷 316-330页

作者： Ke Zhang Suping Wang Chenchen Zhou Lei Cheng Xianling Gao Xianju Xie Jirun Sun Haohao Wang Michael D.Weir Mark A.Reynolds Ning Zhang yuxing bai Hockin H.K.Xu Department of Orthodontics School of Stomatology Capital Medical University Department of Advanced Oral Sciences and Therapeutics University of Maryland Dental School State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Deptartment of Cariology and Endodonics West China Hospital of Stomatology Sichuan University Department of Operative Dentistry and Endodontics Guanghua School of Stomatology Sun Yat-sen University Guangdong Provincial Key Laboratory of Stomatology Volpe Research Center American Dental Association Foundation National Institute of Standards and Technology Center for Stem Cell Biology & Regenerative Medicine University of Maryland School of Medicine Marlene and Stewart Greenebaum Cancer Center University of Maryland School of Medicine

Hard tissue repair and regeneration cost hundreds of billions of dollars annually worldwide, and the need has substantially increased as the population has aged. Hard tissues include bone and tooth structures that contain calcium phosphate minerals.Smart biomaterial-based tissue engineering and regenerative medicine methods have the exciting potential to meet this urgent need. Smart biomaterials and constructs refer to biomaterials and constructs that possess instructive/inductive or triggering/stimulating effects on cells and tissues by engineering the material's responsiveness to internal or external stimuli or have intelligently tailored properties and functions that can promote tissue repair and regeneration. The smart material-based approaches include smart scaffolds and stem cell constructs for bone tissue engineering; smart drug delivery systems to enhance bone regeneration; smart dental resins that respond to pH to protect tooth structures; smart pH-sensitive dental materials to selectively inhibit acid-producing bacteria; smart polymers to modulate biofilm species away from a pathogenic composition and shift towards a healthy composition; and smart materials to suppress biofilms and avoid drug resistance. These smart biomaterials can not only deliver and guide stem cells to improve tissue regeneration and deliver drugs and bioactive agents with spatially and temporarily controlled releases but can also modulate/suppress biofilms and combat infections in wound sites. The new generation of smart biomaterials provides exciting potential and is a promising opportunity to substantially enhance hard tissue engineering and regenerative medicine efficacy.

关键词： regeneration engineering minerals

基于蜂窝铝板的FSAE赛车半单体壳车身结构设计与研究

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山东理工大学学报（自然科学版） 2024年第4期38卷 38-44页

作者：周冲张明陈文臧利国柏宇星南京工程学院汽车与轨道交通学院江苏南京211167

针对FSAE赛车车身结构设计中碳纤维单体壳车身制造工艺复杂、成本高以及传统钢管桁架式车身扭转刚度较低的问题,提出了一种基于蜂窝铝板的新型单体壳车身结构,以实现高扭转刚度和低制造成本的目标。确定了车身扭转刚度和总质量的设计目... 详细信息

针对FSAE赛车车身结构设计中碳纤维单体壳车身制造工艺复杂、成本高以及传统钢管桁架式车身扭转刚度较低的问题,提出了一种基于蜂窝铝板的新型单体壳车身结构,以实现高扭转刚度和低制造成本的目标。确定了车身扭转刚度和总质量的设计目标,并通过人机工程设计确定了车身的基本尺寸;采用有限元分析方法得出了最优的铺层方案,并对车身在各工况下进行了强度校核分析。研究结果表明,铝合金半单体壳车身具有良好的扭转刚度和轻量化水平,是一种性价比优良的新型车身结构,可替代传统的钢管桁架式车身。本研究为FSAE赛车提供了新的车身设计思路。

关键词： FSAE赛车单体壳车身蜂窝铝桁架式车身扭转刚度

面向智能建造专业的项目互动式课程改革探索——以智能感知网为例

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中国现代教育装备 2024年第9期 155-157页

作者：朱颖杰白玉星纪颖波满轲刘心男北方工业大学土木工程学院北京100144

智能建造专业作为新工科专业之一,其交叉学科课程对培养复合型人才具有关键作用,应充分结合工程背景提升学生的自主创新能力和综合实践能力。以智能感知网课程为例,在总结课程现状的基础上,提出了项目互动式教学模式,并取得了良好效果... 详细信息

智能建造专业作为新工科专业之一,其交叉学科课程对培养复合型人才具有关键作用,应充分结合工程背景提升学生的自主创新能力和综合实践能力。以智能感知网课程为例,在总结课程现状的基础上,提出了项目互动式教学模式,并取得了良好效果。相关教学案例可为类似课程提供重要参考。

关键词：智能建造交叉学科教学改革项目互动