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Bionic Design and Analysis of a Novel Quadruped Robot with a Multistage Buffer System

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Chinese Journal of Mechanical Engineering 2022年第2期35卷 56-76页

作者： Yi zheng Kun Xu Yaobin Tian huichao deng.xilun ding School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China

Large quadruped mammals,such as ruminants,have outstanding motion ability,including running and *** advanced motion abilities are related to the buffer effect of their complicated musculoskeletal ***,the buffer effect of most bio-robots is not satisfactory owing to the simple design of their buffer *** this paper,a physiological analysis of the ruminant musculoskeletal system is presented to explain the intrinsic buffer mechanism of *** on the physical buffer parts of the ruminant limbs,the corresponding bionic mappings were *** mappings were used to guide the mechanism design of the robot multistage buffer *** multistage buffer system includes two main buffer mechanisms:the first stage and the second *** buffer mechanism analysis of the first stage and multiple stages is discussed in theory to compare the effects between the normal single buffer system and the novel multistage buffer ***,the detailed mechanical structure of the limbs was designed based on the limb mechanism *** further verify the superior efficacy of the multistage buffer system,the corresponding walking simulation experiments were conducted after the virtual prototype of a quadruped robot with a novel limb was built *** theoretical analysis and simulation experiments prove that the bionic robot design with the novel multistage buffer system achieves better motion performance than the traditional robot buffer design and can be regarded as the design template of the robot limb.

关键词： Ruminant musculoskeletal system Bioinspired multistage buffer system Mechanism design Robotics Quadruped robot

Technologies and studies of gas exchange in two-stroke aircraft piston engine:A review

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Chinese Journal of Aeronautics 2024年第1期37卷 24-50页

作者： Yu ZHOU Xueyu LI Shuiting ding Shuai ZHAO Kun ZHU Longtao SHAO Farong DU Gerui WANG zheng XU Research Institute of Aero-Engine Beihang UniversityBeijing 100191China Aircraft/Engine Integrated System Safety Beijing Key Laboratory Beijing 100191China School of Transportation Science and Engineering Beihang UniversityBeijing 100191China Civil Aviation University of China Tianjin 300300China Aero Engine Academy of China Beijing 101304China School of Energy and Power Engineering Beihang UniversityBeijing 100191China Beihang Hangzhou Innovation Institute yuhang Hangzhou 310052China

The in-cylinder gas exchange process is crucial to the power performance of two-stroke aircraft piston engines,which is easily influenced by complex factors such as high-altitude performance variation and in-cylinder flow *** paper reviews the development history and characteristics of gas exchange types,as well as the current state of theory and the validation methods of gas exchange technology,while also discusses the trends of cutting-edge technologies in the *** paper provides a theoretical foundation for the optimization and engineering design of gas exchange systems and,more importantly,points out that the innovation of gas exchange types,the modification of theoretical models,and the technology of variable airflow organization are the key future research directions in this field.

关键词： Aircraft piston engine Aircraft power systems Gas exchange High-altitude performance In-cylinder flow Two-stroke Unmanned Aerial Vehicles(UAVs)

基于PERK/ATF4/CHOP途径探讨当归补血汤含药血清抑制糖尿病肾病内质网应激改善足细胞凋亡的机制

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中国实验方剂学杂志 2024年第16期30卷 10-18页

作者：顾悦申宇航丁鑫王逸凡张圆圆郑琳琳郭登洲河北中医药大学石家庄050091 北京市通州区潞城社区卫生服务中心北京101100 河北中医药大学第一附属医院/河北省中医院石家庄050011

目的:观察当归补血汤对高糖刺激小鼠永生化足细胞MPC5内质网应激通路蛋白激酶样内质网激酶(PERK)/活化转录因子4(ATF4)/CCAAT增强子结合蛋白同源蛋白(CHOP)及凋亡蛋白B细胞淋巴瘤-2(Bcl-2)、Bcl-2相关X蛋白(Bax)、切割型胱天蛋白酶-3(cl... 详细信息

目的:观察当归补血汤对高糖刺激小鼠永生化足细胞MPC5内质网应激通路蛋白激酶样内质网激酶(PERK)/活化转录因子4(ATF4)/CCAAT增强子结合蛋白同源蛋白(CHOP)及凋亡蛋白B细胞淋巴瘤-2(Bcl-2)、Bcl-2相关X蛋白(Bax)、切割型胱天蛋白酶-3(cleaved Caspase-3)的影响,通过体外研究阐明当归补血汤调控糖尿病肾病(DKD)足细胞凋亡的具体机制及靶点。方法:制备好含药血清、筛选好最适干预浓度后,将小鼠永生化足细胞MPC5分为5组:正常组(NG)、高糖组(HG)、空白血清组(KB)、当归补血汤含药血清组(DBT)、ERS抑制剂组(4-PBA)。NG组中足细胞用含5.5 mmol·L^(-1)葡萄糖的完全培养基培养;HG组中足细胞用含30 mmol·L^(-1)葡萄糖的完全培养基培养;KB组即HG组+10%空白血清;DBT组即HG组+10%当归补血汤含药血清;4-PBA组即HG组+4-PBA(2.5 mmol·L^(-1))。各组予对应药物进行干预刺激,作用48 h,然后将细胞收集。原位末端标记法(TUNEL)测细胞DNA损伤,免疫荧光检测葡萄糖调节蛋白78(GRP78)、磷酸化(p)-PERK、ATF4、CHOP、足细胞膜蛋白(Podocin)、突触足蛋白(Synaptopodin)表达,同时提取足细胞蛋白,蛋白免疫印迹法(Western blot)检测GRP78、PERK、p-PERK、真核翻译起始因子2α(eIF2α)、p-eIF2α、ATF4、CHOP、Bcl-2、Bax、cleaved Caspase-3蛋白表达。结果:与正常组比较,高糖组GRP78、p-PERK、ATF4和CHOP荧光强度显著增加,Podocin、Synaptopodin荧光强度减弱,足细胞TUNEL荧光阳性细胞核明显增多,GRP78、p-PERK/PERK、p-eIF2α/eIF2α、ATF4、CHOP、Bax、cleaved Caspase-3蛋白表达显著上升,Bcl-2表达显著下降(P<0.01)。与高糖组比较,当归补血汤含药血清组及ERS抑制剂组GRP78、p-PERK、ATF4和CHOP的荧光强度明显减弱,Podocin、Synaptopodin荧光表达增强,TUNEL阳性染色细胞核的数量明显减少,细胞核损伤减轻,GRP78、p-PERK/PERK、p-eIF2α/eIF2α、ATF4、CHOP、Bax、cleaved Caspase-3蛋白表达显著下调,Bcl-2蛋白表达显著升高(P<0.01)。高糖组和空白血清组以上结果比较差异无统计学意义。结论:当归补血汤含药血清可通过拮抗PERK/ATF4/CHOP信号通路的活化实现对足细胞凋亡的抑制,保护足细胞。

关键词：当归补血汤糖尿病肾病足细胞凋亡蛋白激酶样内质网激酶(PERK)/活化转录因子4(ATF4)/CCAAT增强子结合蛋白同源蛋白(CHOP)信号通路

Skin mimicking-sweating evaporation polyimide cooling film for electronic devices

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Science China(Technological Sciences) 2023年第10期66卷 2797-2807页

作者： JIANG Miao XIAO Chao HE XuSheng DU huichao WANG YanYan ding Xin ZHANG Xian LI XiaoFei zheng Kang LIU XiangLan CHEN Lin TIAN XingYou Key Lab of Photovoltaic and Energy Conservation Materials Institute of Solid State PhysicsHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China Science Island Branch University of Science and Technology of ChinaHefei 230026China Lu’an Branch Anhui Institute of Innovation for Industrial TechnologyLu’an 237000China School of Materials Science and Engineering Anhui UniversityHefei 230039China

In hot environments,the human body shows an efficient capability to maintain a stable temperature by benefiting from sweating *** by this skin perspiration strategy,in this study,we demonstrated an innovative polyimide foam(PIF)-based mimetic skin with excellent cooling capability by integrating a silver coating and reusable hydrogel for the first *** of the hybrid thermal dissipating system,the successive silver coating quickly transferred heat to the inside of the polyacrylamide ***,the hydrogel absorbed a large amount of heat due to its large enthalpy and effectively dissipated heat to the environment through the evaporation of moisture,similar to the sweating of ***,the temperature of the skin-like film was reduced by 25.4℃compared with pure PIF under a high-power laser heating *** and remarkable cooling effects were also obtained in mobile phone and battery applications,far better than commercially available thermally conductive polyimide(PI).This outstanding performance paves a new way for the thermal management application of PI in wearable electronics,microprocessors,and flexible electronics.

关键词： skin-mimicking polyimide hydrogel thermal management sweat cooling

Porous polyimide-based phase change materials with enhanced mechanical properties, thermal conductivity, and thermal shock resistance through precisely designed triple-functional layers

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中国科学:技术科学英文版 2023年第9期66卷 2716-2724页

作者： JIANG Miao XIAO Chao ding Xin WANG YanYan ZHANG Xian DU yuhang LI XiaoFei zheng Kang LIU XiangLan CHEN Lin TIAN XingYou Key Lab of Photovoltaic and Energy Conservation Materials Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China Science Island Branch University of Science and Technology of ChinaHefei 230026China Lu’an Branch Anhui Institute of Innovation for Industrial TechnologyLu’an 237000China

Numerous scenarios of direct contact between electronic components and skin appear in wearable electronic devices. As the “second skin” that lies next to the biological skin of the human body, flexible wearable devices need to be equipped with thermal protection. However, the use of flexible phase change materials(PCMs) for wearable devices remains a challenge due to their low thermal conductivity, weakened mechanical strength, and liquid leakage. Herein, we developed a multilayered polyimide(PI) composite film integrating stable latent heat absorption, high thermal conductivity, and enhanced mechanical strength. This single piece of material achieved more prominent hotspot protection than traditional foams. The in-plane thermal conductivity of the resultant substrate layer is up to 2.655 W/(m K), which provides a fast response and in-plane dissipation for heat flow. The deliberately arranged interlayer of the material significantly improved the tensile strength(37.6 MPa) of the composite film,representing 128.9% greater strength than that of a bilayer film without a dense layer. The top layer with abundant pores provides reversibly latent heat storing and releasing function after being well infiltrated with paraffin wax. The resulting synergistic effect between three functional layers shows superb heat-suppressing performance in the thickness direction in both thermal shockresistant tests and simulation results. Impressively, the maximum temperature drop reached 40.2℃ compared with the pure PI film. The heating time was delayed by 12 s, providing sufficient warning time for human emergency response. This strategy can potentially pave the way for the design and fabrication of multifunctional films for wearable electronics in thermal protection applications.

关键词： foams layered structures thermal properties thermal analysis

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单季稻开花结实期高温热害特征及防控对策

中国稻米 2024年第4期30卷 98-100页

作者：方文英陈佳麒楚岱蔚丁梦佳姚平金益民罗天子沈兴连莫红华黄玉英郑孝孝朱德峰杭州市余杭区农业技术推广中心杭州311114 杭州市余杭区气象局杭州311121 杭州市余杭区瓶窑镇区域发展办公室杭州311115 杭州市余杭区良渚街道区域发展办公室杭州311113 杭州余杭区瓶窑镇罗欢家庭农场杭州311115 杭州余杭益民农业生产服务专业合作社杭州311107 杭州宇帆农业发展专业合作社杭州311121 中国水稻研究所杭州310006

近年,长江流域稻区单季稻开花结实期高温频发重发。本文分析了高温年水稻开花结实期高温热害特征及高温对结实率的影响。高温年日最高温度高,持续时间延长;高温年7月上旬至8月上旬日最高温度较常温年高4.3℃~4.8℃;水稻开花结实期遇到... 详细信息

近年,长江流域稻区单季稻开花结实期高温频发重发。本文分析了高温年水稻开花结实期高温热害特征及高温对结实率的影响。高温年日最高温度高,持续时间延长;高温年7月上旬至8月上旬日最高温度较常温年高4.3℃~4.8℃;水稻开花结实期遇到高温热害结实率下降28.2~43.4个百分点;品种间耐高温热害特性差异较大。根据开花结实期高温热害特征及高温引起结实率下降的特点,提出高温预警及播期调整、耐热品种选择、高温期间田间灌水、喷施生长调节物质等开花结实期高温热害防控对策。

关键词：单季稻开花结实期高温热害长江流域

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动态和静态测试定向刨花板的泊松比

林业科学 2021年第8期57卷 147-156页

作者：王正黄俣劼许斌丁叶蔚张一凡何宇航周宇昊南京林业大学材料科学与工程学院南京210037

【目的】探讨悬臂板一阶弯曲模态法(动态法)和悬臂板静力弯曲法(静态法)测试定向刨花板(OSB)纵向和横向泊松比的适用性,给出动态法测试OSB纵向和横向泊松比的贴片位置。【方法】应用ANSYS模态程序块和静力弯曲程序块对OSB悬臂板进行动... 详细信息

【目的】探讨悬臂板一阶弯曲模态法(动态法)和悬臂板静力弯曲法(静态法)测试定向刨花板(OSB)纵向和横向泊松比的适用性,给出动态法测试OSB纵向和横向泊松比的贴片位置。【方法】应用ANSYS模态程序块和静力弯曲程序块对OSB悬臂板进行动、静态应力和应变分析,计算长宽比3~6、宽厚比4~10的OSB纵向和横向悬臂板的应力和应变;确定悬臂板内横向应力等于零的位置,即动态和静态测试OSB纵向和横向泊松比的应变片粘贴位置,并应用二元回归分析将其表示为依赖于悬臂板试件长宽比和宽厚比的关系式。【结果】对于国产和加拿大产OSB,动态测试的纵向泊松比分别为0.342和0.314,横向泊松比分别为0.131和0.174;动态和静态测试OSB泊松比的贴片位置虽不同,但测试出的泊松比较为一致。【结论】悬臂板一阶弯曲模态法和悬臂板静力弯曲法适用于测试OSB纵向和横向泊松比,其有效性得到轴向拉伸法和四点弯曲法的验证。

关键词：定向刨花板泊松比动态静态

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高渗透选择性纳滤膜的制备及其分盐性能

膜科学与技术 2022年第2期42卷 103-109页

作者：丁华烘郑彤葛宇航刘梅红俞三传杭州求是膜技术有限公司杭州311121 浙江理工大学理学院杭州310018

以鞣酸(TA)作为第二水相反应材料,通过TA分子与初生态聚酰胺(PA)复合膜表面残余酰氯的酯化反应,调节分离层的物理化学性质和微观结构,研究二次界面反应对复合纳滤膜性能的影响,制备高渗透选择性纳滤膜.结果表明:TA分子通过酯化反应实现... 详细信息

以鞣酸(TA)作为第二水相反应材料,通过TA分子与初生态聚酰胺(PA)复合膜表面残余酰氯的酯化反应,调节分离层的物理化学性质和微观结构,研究二次界面反应对复合纳滤膜性能的影响,制备高渗透选择性纳滤膜.结果表明:TA分子通过酯化反应实现在初生态聚酰胺分离层表面的致密沉积;与PA分离层相比,PA-TA分离层具有更小的孔径、更窄的孔径分布和更强的表面电负性;在最优制备条件下,含PA-TA分离层的复合膜的切割分子量为210 g/mol、纯水渗透率为120 L/(m^(2)·h·MPa);在0.5 MPa下,对0.5 g/L单一溶质水溶液硫酸钠截留率高达99.3%、氯化钠截留率为60.2%;在3.0 MPa、40℃下,PA-TA复合膜过滤含200 g/L NaCl和10.0 g/L Na_(2)SO_(4)的水溶液,在浓缩倍率5倍下,对硫酸钠平均截留率大于98.5%,平均水通量达120 L/(m^(2)·h);而对氯化钠几乎无截留;对氯化钠和硫酸钠混合盐溶液的分盐性能优于NF270.

关键词：纳滤膜界面聚合渗透选择性浓盐水

Dy^(3+)和Eu^(3+)共掺NaY(MoO_(4))_(2)荧光粉合成与发光性能研究

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量子电子学报 2023年第1期40卷 32-39页

作者：童叶郑宇航刘文鹏丁守军安徽工业大学数理科学与工程学院安徽马鞍山243002 先进激光技术安徽省实验室安徽合肥230037 中国科学院合肥物质科学研究院安徽光学精密机械研究所安徽合肥230026

用高温固相法制备了一系列2 at.%Dy^(3+)和x at.%Eu^(3+)(x=0,0.1,0.5,1,2,5)共掺NaY(MoO_(4))_(2)样品。X射线衍射(XRD)、扫描电子显微镜(SEM)及红外光谱(FTIR)表征结果表明所合成的样品为四方相结构,空间群为I41/a。进一步研究了样品... 详细信息

用高温固相法制备了一系列2 at.%Dy^(3+)和x at.%Eu^(3+)(x=0,0.1,0.5,1,2,5)共掺NaY(MoO_(4))_(2)样品。X射线衍射(XRD)、扫描电子显微镜(SEM)及红外光谱(FTIR)表征结果表明所合成的样品为四方相结构,空间群为I41/a。进一步研究了样品的激发光谱和在近紫外光激发下的发射特性,结果表明Dy^(3+)和Eu^(3+)之间存在能量共振传递,从而增强了Eu^(3+)的发光。2 at.%Dy^(3+)和2 at.%Eu^(3+)共掺样品的CIE色度坐标值(x=0.659,y=0.338)接近NTSC规定的标准值,因而有望作为显色性能优良的发光材料用于固态照明领域。此外,NaY(MoO_(4))_(2)物化性能稳定,易采用提拉法生长,因此本研究结果可以为Dy^(3+)和Eu^(3+)共掺NaY(MoO_(4))_(2)单晶生长以及蓝紫光泵浦可见激光特性研究提供参考。

关键词：材料高温固相法 NaY(MoO_(4))_(2) 能量共振传递固态照明