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基于后缘小翼的翼型动态失速主动控制试验

航空学报 2024年第3期45卷 105-120页

作者：李国强宋奎辉覃晨赵光银吴霖鑫杨永东国防科技大学空天科学学院长沙410073 中国空气动力研究与发展中心低速空气动力研究所绵阳621000

针对旋翼动态失速导致的非定常载荷增加和失速颤振问题,开展了基于后缘小翼的翼型动态失速主动控制试验,试验雷诺数Re=7.0×10^(5),减缩频率k=0.097。采用动态压力测试手段,重点分析了后缘小翼不同振荡相位差、幅值、平衡迎角对翼型动... 详细信息

针对旋翼动态失速导致的非定常载荷增加和失速颤振问题,开展了基于后缘小翼的翼型动态失速主动控制试验,试验雷诺数Re=7.0×10^(5),减缩频率k=0.097。采用动态压力测试手段,重点分析了后缘小翼不同振荡相位差、幅值、平衡迎角对翼型动态失速的影响规律。结果表明,后缘小翼能以振荡周期T的1/2为时间间隔,周期交替地改变翼型的气动性能,在后缘小翼与翼型振荡相位差为0°的条件下,实现了俯仰力矩峰值降低54.9%的控制效果,同时更大的后缘小翼振荡幅值能实现更好的非定常载荷控制效果,但过大的振荡幅值有可能导致失速颤振。后缘小翼振荡平衡迎角的引入能起到调节升力系数、气动阻尼的作用。

关键词：后缘小翼动态失速失速颤振气动阻尼旋翼

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股骨骨缺损动物模型制备现状及特点

中国组织工程研究 2024年第4期28卷 633-638页

作者：周世博关健斌俞兴赵赫杨永栋刘涛北京中医药大学第一临床医学院北京市100029 北京中医药大学东直门医院北京市100070

背景:骨缺损的修复及后期临床转归仍是临床研究中的热点和难点,是困扰临床医师的常见问题。构建合适、可重复性及无限接近临床的动物实验模型及科学的评估对进一步的临床治疗相关疾病至关重要。目的:回顾性分析文献中股骨骨缺损常用实... 详细信息

背景:骨缺损的修复及后期临床转归仍是临床研究中的热点和难点,是困扰临床医师的常见问题。构建合适、可重复性及无限接近临床的动物实验模型及科学的评估对进一步的临床治疗相关疾病至关重要。目的:回顾性分析文献中股骨骨缺损常用实验动物模型制备方法及不同模型特点,评估优势与不足,为相关研究者选择合适的股骨骨缺损动物模型提供一定的参考。方法:检索PubMed、Web of Science、Medline数据库及CNKI数据库,设定英文检索词为:bone defect,bone,bones,defect,defects,defective,animal model,animal,model,laboratory,laboratory animal,animal laboratory;中文检索词为:骨缺损,动物模型,实验。检索时限为2000-01-01/2022-08-01。结果与结论:①对入选的27篇随机对照动物实验进行了分析和评估,实验动物包含大鼠、小鼠、新西兰兔及羊,骨缺损类型主要包含圆柱形骨缺损和节段性截骨骨缺损,部位以股骨中段及远端居多。多用于评估骨修复材料、药物、载药活性物质及物理治疗等方法对骨缺损修复的影响及缺损愈合机制研究,尤其是负重骨缺损修复机制的研究。②不同缺损类型及不同实验动物股骨骨缺损值的范围不同,研究者可结合实验目的,选择合适的动物及骨缺损类型,并设置合理的骨缺损值。③目前的研究表明,股骨骨缺损模型以圆柱形及节段截骨骨缺损为主,主要是在股骨远端及中段,手术方法及术后处理较为成熟,可操作性强,能够提供成熟的实验动物模型。④就圆柱形骨缺损而言,大鼠及新西兰兔更适合,而节段性截骨则无特殊要求,各种动物均能满足实验要求。

关键词：股骨骨缺损动物模型评估临界性骨缺损

氧化铝纤维掺量及长度对混凝土力学性能和微观结构的影响

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硅酸盐通报 2024年第8期43卷 2871-2878页

作者：吕圆芳闫铁成杨永东卢同平陇东学院土木工程学院庆阳745000 北京大学城市与环境学院北京100080

氧化铝纤维(AOF)是一种新型多晶陶瓷纤维材料,具有较好的亲水性。以AOF为改性材料,制备了氧化铝纤维改性混凝土(AOFMC),通过测试AOFMC的抗压强度、抗折强度和劈拉强度,分析了AOF掺量和长度对混凝土力学性能的影响,确定了AOF的最佳掺量... 详细信息

氧化铝纤维(AOF)是一种新型多晶陶瓷纤维材料,具有较好的亲水性。以AOF为改性材料,制备了氧化铝纤维改性混凝土(AOFMC),通过测试AOFMC的抗压强度、抗折强度和劈拉强度,分析了AOF掺量和长度对混凝土力学性能的影响,确定了AOF的最佳掺量和长度。在此基础上,研究了AOF对不同强度等级混凝土(C40、C50、C60)力学性能的增强作用。此外,结合扫描电子显微镜和压汞试验,分析了AOF对混凝土微观结构的影响。结果表明:AOF掺量和长度对混凝土力学性能的提高效果相互制约,当AOF长度为12 mm、体积掺量为0.2%时,AOFMC的力学性能最佳;随着强度等级的增大,AOF对混凝土力学性能的提高效果不断增大;AOF与混凝土基体结合良好,从而提高了混凝土的力学性能;在C50混凝土中,AOF主要被拔出,而在C60混凝土中,AOF部分被拉断;当AOF长度较小时,AOF可以填充混凝土内部孔隙。

关键词：混凝土氧化铝纤维长度掺量力学性能微观结构

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获得性异位骨化的分子生物学机制

中国组织工程研究 2024年第30期28卷 4881-4888页

作者：熊洋周世博俞兴毕连涌杨济洲王逢贤曲弋杨永栋赵丁岩赵赫仇子叶姜国正北京中医药大学东直门医院骨科北京市100700

背景:异位骨化是一个动态发展的过程,临床中不同亚型的异位骨化具有不同病因或诱导因素,但在异位骨化中后期进展阶段又表现出相似的病理过程,其中由于创伤等因素引起的获得性异位骨化具有较高的发病率。目的:对近年获得性异位骨化发生... 详细信息

背景:异位骨化是一个动态发展的过程,临床中不同亚型的异位骨化具有不同病因或诱导因素,但在异位骨化中后期进展阶段又表现出相似的病理过程,其中由于创伤等因素引起的获得性异位骨化具有较高的发病率。目的:对近年获得性异位骨化发生发展相关分子生物学机制研究进行综述。方法:以“分子生物学,异位骨化,机制”为检索词在中国知网、万方医学数据库进行检索,以“molecular biological,heterotopic ossification,mechanisms”为检索词分别在PubMed、Embase、Web of Science及Google Scholar数据库进行检索,检索时限为2016年1月至2022年8月,并根据获得文献进行补充检索,对所得文献进行筛选,最终纳入131篇文献进行综述分析。结果与结论:①获得性异位骨化的发生和发展是一个动态的过程,具有一定的隐匿性,因此该疾病的诊疗有一定的困难。②文章通过综述国内外相关文献,发现获得性异位骨化涉及骨形态发生蛋白、转化生长因子β、Hedgehog、Wnt及mTOR共5条主要信号通路,同时在局部微环境中涉及到Runx2、血管内皮生长因子、缺氧诱导因子、成纤维细胞生长因子及Sox9共5项核心枢纽因子,核心机制可能是不同信号通路之间的相互作用,影响机体成骨细胞前体细胞、成骨细胞微环境以及与此相关的细胞因子,进而影响机体骨代谢并导致获得性异位骨化的发生。③未来可以以异位骨化相关单细胞的成骨内稳态为研究方向,以成骨细胞前体细胞-成骨微环境-信号通路及细胞因子作为研究要素,探索各部分要素在不同时空条件下的特征,比较不同种类、不同个体细胞成骨内稳态异同,从整体视角观察异位骨化分子信号网络调控机制,有利于未来临床防治异位骨化新方法的探究。④以中医药及靶向治疗为代表的治疗方法是近年的研究热点,如何将中医药与体内成骨稳态联系,并与靶向治疗相结合,也是未来研究方向之一。⑤目前获得性异位骨化的研究仍多限于基础实验研究,临床防治方法仍存在疗效不确切及不良反应明显等缺陷,相关靶向防治药物临床应用安全性及有效性仍有待验证,如何以基础实验研究为基础,结合发生发展机制,为临床防治提供新方向将是未来研究的重点。

关键词：异位骨化分子生物学机制骨形态发生蛋白转化生长因子β Hedgehog Wnt/β-catenin Runt相关转录因子2 血管内皮生长因子低氧诱导因子成纤维细胞生长因子

Dynamic stall control over a rotor airfoil based on AC DBD plasma actuation

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Advances in Aerodynamics 2021年第1期3卷 153-165页

作者： Guangyin Zhao Yong Huang yongdong yang Guoqiang Li Hesen yang State Key Laboratory of Aerodynamics China Aerodynamics Research and Development CenterMianyang 621000China Low Speed Aerodynamics Institute China Aerodynamics Research and Development CenterMianyang 621000China Science and Technology on Plasma Dynamics Laboratory Air Force Engineering UniversityXi’an 710038China.

At present,the control capability of dielectric barrier discharge(DBD)plasma actuation covers the flow velocity range of helicopter’s retreating blades,so it is necessary to extend it to the dynamic stall control of rotor airfoils.A DBD plasma actuator was adopted to control the dynamic stall of an oscillating CRA309 airfoil in this *** effectiveness of alternating current(AC)DBD plasma actuation on reducing the area of lift hysteresis loop of the oscillating airfoil was verified through pressure measurements at a Reynolds number of 5.2×10^(5).The influence of actuation parameters on the airfoil’s lift and moment coefficients was *** steady and unsteady actuation could effectively reduce the hysteresis loop area of the lift *** flow control effect of dynamic stall was strongly dependent on the history of angle of *** with the steady actuation,unsteady actuation had more obvious advantages in dynamic stall control,with reducing the area of lift hysteresis loop by more than 30%.The effects of plasma actuation on the airfoil’s flow field at both upward and downward stages were discussed at last.

关键词： Plasma actuation Flow separation Dynamic stall Hysteresis Dielectric barrier discharge

Application of PMMA bone cement composited with bone-mineralized collagen in percutaneous kyphoplasty

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Regenerative Biomaterials 2017年第4期4卷 251-255页

作者： Ming Bai Heping Yin Jian Zhao yang Li yongdong yang Yimin Wu Department of Minimally Invasive Spinal Surgery of the Second Affiliated Hospital of Inner Mongolia Medical University Hohhot 010030China Inner Mongolia Medical University Hohhot 010030China Institute for Regenerative Biomaterials Tsinghua UniversityBeijing 100084China

We investigated the feasibility of applying polymethylmethacrylate bone cement composited with biomimetic bone-mineralizsed collagen to percutaneous kyphoplasty(PKP).We performed PKP in 95 patients diagnosed with osteoporotic vertebral compression *** patients had fractures of a single vertebral body,and they were divided randomly into control(group A,47 patients)and experimental(group B,48 patients)*** in group A were treated with acrylic cement,and those in group B were treated with acrylic cement composited with the bone graft *** patients were evaluated by a visual analogue scale(VAS),Oswestry disability index(ODI),Cobb angle and anterior vertebral body height preoperatively,and 3 days and 3 months *** patients successfully completed surgery and were followed up *** VAS score,ODI index,Cobb angle and anterior vertebral body height compression rate in both groups had significant changes(P0.05).The analgesic effects of bone cement composited with bone-mineralized collagen are similar to those of bone cement *** collagen has excellent promotion prospects by inducing new bone formation and reducing the incidence of adverse reactions caused by bone cement.

关键词： percutaneous kyphoplasty osteoporotic vertebral compression fractures bone cement mineralized collagen

Mineralization of calcium phosphate controlled by biomimetic selfassembled peptide monolayers via surface electrostatic potentials

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Bioactive Materials 2020年第2期5卷 387-397页

作者： Shuo Wang yongdong yang Ronghan Wang Xiangdong Kong Xiumei Wang State Key Laboratory of New Ceramics and Fine Processing Key Laboratory of Advanced Materials of Ministry of EducationSchool of Materials Science and EngineeringTsinghua UniversityBeijing100084China Dongzhimen Hospital Affiliated Beijing University of Chinese Medicine Beijing100700China College of Life Sciences Zhejiang Sci-Tech UniversityHangzhou310018China

The functions of acidic-rich domains in non-collagenous protein during biomineralization are thought to induce nucleation and control the growth of *** tripeptide Asp-Ser-Ser(DSS)repeats are the most common acidic-rich repeated unit in non-collagenous protein of dentin phosphoprotein,the functions of which have aroused extensive *** this study,biomimetic peptides(DSS)n(n=2 or 3)were designed and fabricated into self-assembled monolayers(SAMs)on Au(111)surface as biomimetic organic templates to regulate hydroxyapatite(HAp)mineralization in 1.5 simulated body fluid(1.5 SBF)at 37°*** early mineralization processes and minerals deposited on the SAMs were characterized by X-ray diffraction,scanning electron microscope,and Fourier transform infrared spectroscopy *** SAM-DSS9/DSS9G showed the highest capacity to induce HAp nucleation and growth,followed by SAM-DSS6/DSS6G,SAM-COOH,and *** SAM-(DSS)n had more negative zeta potentials than SAM-COOH surface,indicating that DSS repeats contributed to the biomineralization,which not only provided strong affinity with Ca2+ions through direct electrostatic bonds,but more importantly influence surface electrostatic potentials of the assembled organic template for nucleation.

关键词： Hydroxyapatite Biomineralization Self-assembled monolayer Oligopeptides Dentin phosphoprotein

Bifunctional two-carbon reagent made from acetylene via 1,2-difunctionalization and its applications

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Science China Chemistry 2024年第3期67卷 936-944页

作者： Bo yang Kangkui Li yongdong Wang Shifa Zhu Key Laboratory of Functional Molecular Engineering of Guangdong Province School of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhou 510640China School of Chemistry and Chemical Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China Singfar Laboratories Guangzhou 510670China

There are very limited approaches to directly gluing two molecules for the production of internal alkenes using the vastly abundant acetylene via 1,2-difunctionalization. Conversion of gaseous acetylene to internal alkenes via 1,2-difunctionalization in a desired manner is not as easy as it might be expected due to the potential competition reactions between acetylene and alkene produced and the difficulty in handling this harmful reagent and controlling the regio-and stereoselectivity. In this work, we designed an efficient catalytic system for the incorporation of acetylene gas into tremendous(E)-β-bromo vinylsulfones, which are bench-stable, easy to operate, and can function as bifunctional acetylene and show a rich reactivity profile in Sonogashira coupling, Heck coupling, substituted reaction, and various desulfonylation transformations, providing numerous internal alkenes.

关键词： acetylene 1 2-difunctionalization photocatalysis vinylsulfone

Effects of electroacupuncture combined with hydrogel on the formation and changes in the glial scar in rats with spinal cord injury

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Journal of Traditional Chinese Medical Sciences 2022年第2期9卷 197-205页

作者： Kaitan yang Yushan Gao yongdong yang Chuanhong Li Zheng Cao Xiumei Wang Zaibo Li Xing Yu Ward Three Department of OrthopedicsBeijing University of Chinese Medicine Dongzhimen Hospital100010BeijingChina School of Traditional Chinese Medicine Beijing University of Chinese Medicine100029BeijingChina School of Materials Science and Engineering Tsinghua University100084BeijingChina Department of Pathology The OHIO State University Wexner Medical CenterColumbusOH43210USA

Objective: To observe the effect of electroacupuncture(EA) combined with oriented conductive bioprotein hydrogel(OCBH) on the recovery of nerve function in rats with complete spinal cord injury(SCI)and to explore its effect and mechanism on the formation and changes of glial ***: A total of 72 female Sprague-Dawley rats were randomly divided into groups according to the treatment received. A rat model of complete SCI was constructed using a spinal cord *** assessments, hematoxylin-eosin(H&E) staining, immunofluorescence staining, and Western blotting were performed at a fixed period after the ***: The material group and the material + EA group obtained better results in the behavioral assessments(all P <.05) and the H&E staining. In the immunofluorescence staining and Western blotting,the GFAP protein was expressed more and denser in the material group and the material + EA group than in the model group, and the density of the GFAP expression in the material + EA group was lower at week 12 than in the material group(all P <.05). The expression of complement C3 in the model, material,and material + EA groups decreased in turn. Some inflammatory factors and the NF-κB signaling pathway showed similar results in the Western blotting(all P <.05). The expression of the GDNF protein in the material + EA group was significantly higher than that in the model group and the material group(both P <.01).Conclusion: EA combined with OCBH can promote the recovery of motor functions after SCI by facilitating the formation of glial scars in the early stage, preventing the further spread of an inflammatory response that would affect the activation of A1/A2 astrocytes and change the morphology of glial scars at the spinal cord-material interface in its late stage.

关键词： Spinal cord injury Glial scar Astrocytes Electroacupuncture Jiaji acupoints Hydrogel