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Design Schemes and Comparison Research of the End-effector of Large Space Manipulator

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Chinese Journal of Mechanical Engineering 2012年第4期25卷 674-687页

作者： feng fei LIU Yiwei LIU Hong CAI Hegao State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin 150080 China

The end-effector of the large space manipulator is employed to assist the manipulator in handling and manipulating large payloads on ***,there are few researches about the end-effector,and the existing end-effectors have some disadvantages,such as poor misalignment tolerance capability and complex mechanical *** to the end positioning errors and the residual vibration characters of the large space manipulators,two basic performance requirements of the end-effector which include the capabilities of misalignment tolerance and soft capture are *** the end-effector should accommodate the following misalignments of the mechanical *** translation misalignments in axial and radial directions and the angular misalignments in roll,pitch and yaw are ±100 mm,100 mm,±10°,±15°,±15°,*** end-effector schemes are presented and the capabilities of misalignment tolerance and soft capture are analyzed *** three fingers-three petals end-effector and the steel cable-snared end-effector are the most feasible schemes among the seven schemes,and they are designed in *** capabilities of misalignment tolerance and soft capture are validated and evaluated,through the experiment on the micro-gravity simulating device and the dynamic analysis in ADAMS *** results show that the misalignment tolerance capabilities of these two schemes could satisfy the *** the translation misalignment tolerances in axial and radial directions and the angular misalignment tolerances in roll,pitch and yaw of the steel cable-snared end-effector are 30mm,15mm,6°,3° and 3° larger than those of the three fingers-three petals end-effector,*** the contact force of the steel cable-snared end-effector is smaller and smoother than that of the three fingers-three petals *** end-effector schemes and research methods are beneficial to the developments of the large space manipulator end-effctor and t

关键词： end-effector large space manipulator docking mechanism soft capture misalignment tolerance passive compliance active compliance

Technical assessment of synthetic natural gas (SNG) production from agriculture residuals

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Journal of Thermal Science 2013年第4期22卷 359-365页

作者： Guohui Song fei feng Jun Xiao Laihong Shen Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy and Environment Southeast University Department of Mechanical Technology Nanjing College of Chemical Technology

This paper presents thermodynamic evaluations of the agriculture residual-to-SNG process by thermochemical conversion, which mainly consists of the interconnected fluidized beds, hot gas cleaning, fluidized bed methanation reactor and Selexol absorption unit. The process was modeled using Aspen Plus soft-ware. The process performances, i.e., CH4 content in SNG~ higher heating value and yield of SNGexergy efficiencies with and without heat recovery, unit power consumption, were evaluated firstly. The results indicate that when the other parameters remain unchanged, the steam-to-biomass ratio at carbon boundary point is the optimal value for the process. Im proving the preheating temperatures of air and gasifying agent is beneficial for the SNG yield and exergy effi ciencies. Due to the effects of COz removal efficiency, there are two optimization objectives for the SNG produc tion process：（I） to maximize CH4 content in SNC or （II） to maximize SNG yield. Further, the comparison among different feedstocks indicates that the decreasing order of SNG yield is： corn stalk 〉 wheat straw 〉 rice straw. The evaluation on the potential of agriculture-based SNG shows that the potential annual production of agriculture re sidual-based SNG could be between 555 108 - 611 108 m3 with utilization of 100% of the available unexplored resources. The agriculture residual-based SNG could play a significant role on solving the big shortfall of China＇s natural gas supply in future.

关键词： synthetic natural gas agriculture residual biomass gasification methanation fluidized bed exergy

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贵州某水电站水轮发电机组自动化改造

水电站机电技术 2024年第5期47卷 27-29页

作者：王进费林凤罗湖贵州众诚天河水利工程有限公司贵州毕节551700

随着社会经济的发展和技术进步,水电站作为再生能源的重要生产基地,面临着提高发电效率、确保安全运行和降低运维成本的挑战。以贵州某水电站水轮发电机组为研究对象,为解决其效率、安全性和成本管理等方面的问题,首先分析了当前水电站... 详细信息

随着社会经济的发展和技术进步,水电站作为再生能源的重要生产基地,面临着提高发电效率、确保安全运行和降低运维成本的挑战。以贵州某水电站水轮发电机组为研究对象,为解决其效率、安全性和成本管理等方面的问题,首先分析了当前水电站水轮发电机组的运行状态和自动化改造需求,提出了相应的自动化改造策略,实现了水轮发电机组运行水电站作为再生能源的重要生产基地,效率的显著提升,设备运行的可靠性和安全性得到了增强,同时运维成本得到了有效控制,提升了运维效率,可为相关人员提供借鉴参考。

关键词：水电站水轮发电机组自动化效率管理

二硫化钼负载泡沫镍铁电极降解水中氟苯尼考的研究

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现代化工 2024年第6期44卷 161-167,174页

作者：耿凤飞崔智杰王鹏旭徐剑晖东莞理工学院生态环境与建筑工程学院广东东莞523808 沈阳市化工学校辽宁沈阳110122 洛阳市栾川县水利局河南洛阳471599

以二硫化钼(MoS_(2))为载体,通过水热法负载泡沫镍铁制备MoS_(2)负载泡沫镍铁电极(MoS_(2)@Ni-Fe-Foam)并用于降解水中的氟苯尼考(FLO)。利用X-射线衍射仪(XRD)、扫描电子显微镜(SEM)和X-射线光电子能谱仪(XPS)对电极的表面形貌和元素... 详细信息

以二硫化钼(MoS_(2))为载体,通过水热法负载泡沫镍铁制备MoS_(2)负载泡沫镍铁电极(MoS_(2)@Ni-Fe-Foam)并用于降解水中的氟苯尼考(FLO)。利用X-射线衍射仪(XRD)、扫描电子显微镜(SEM)和X-射线光电子能谱仪(XPS)对电极的表面形貌和元素分布进行表征,采用循环伏安法和电化学阻抗谱对其电化学性能进行表征,通过电子顺磁共振检测(EPR)、高效液相色谱-三重四极杆质谱仪、离子色谱及电化学检测研究了不同条件对FLO降解效果的影响,并对降解产物和降解机理进行了分析。结果表明,当FLO质量浓度为25 mg/L、电流密度为30 mA/cm^(2)、初始pH为3、Na_(2)SO_(4)浓度为30 mmol/L时对FLO的降解速率最快,降解率达到96%。自由基淬灭实验表明,·O_(2)^(-)在降解过程中发挥主要作用,其次是^(1)O_(2),而·OH的影响较弱。最后,通过三重四极杆质谱仪分析得到4种FLO降解产物,并提出FLO的降解机理。

关键词：二硫化钼氟苯尼考电催化水热法

Effect of cooling rate during quenching on the microstructure and creep property of nickel-based superalloy FGH96

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International Journal of Minerals,Metallurgy and Materials 2019年第4期26卷 493-499页

作者： Ye-fei feng Xiao-ming Zhou Jin-wen Zou Gao-feng Tian Science and Technology on Advanced High Temperature Structural Materials Laboratory Beijing Institute of Aeronautical Materials

The effect of cooling rate during quenching on the microstructure and creep property of nickel-based superalloy FGH96 was investigated. Three groups of samples were quenched continuously with three fixed cooling rates, respectively, then subjected to a creep test under a constant load of 690 MPa at 700℃. Clear differences in size of secondary γ′ precipitates, creep properties and substructure of creep-tested samples were observed. The quantitative relationship among cooling rate, the size of secondary γ′ precipitates, and steady creep rate was constructed. It was found that with increasing cooling rate, the size of secondary γ′ precipitates decreases gradually, showing that the relationship between the size of secondary γ′ precipitates and the cooling rate obeys a power law, with an exponent of about –0.6, and the creep rate of steady state follows a good parabola relationship with cooling γ′ precipitate size. For 235℃/min, FGH96 alloy exhibited very small steady creep rate. The density of dislocation was low, and the isolated stacking fault was the dominant deformation mechanism. With decreasing cooling rates, the density of dislocation increased remarkably, and deformation microtwinning was the dominant deformation process. Detailed mechanisms for different cooling rate were discussed.

关键词： quantitative relationship cooling rate secondaryγ′precipitates steady creep rate deformation mechanism

Inhibitory effects of polyphyllins I and VII on human cisplatin-resistant NSCLC via p53 upregulation and CIP2A/AKT/mTOR signaling axis inhibition

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Chinese Journal of Natural Medicines 2019年第10期17卷 768-777页

作者： feng fei-fei CHENG Peng SUN Chao WANG Hui WANG Wei Department of Respiratory Medicine The Second Hospital of Shandong UniversityJinan 250033China Department of Neural Medicine The Second Hospital of Shandong UniversityJinan 250033China Department of Central Laboratory The Second Hospital of Shandong UniversityJinan 250033China

Cancerous inhibitor of protein phosphatase 2A(CIP2A) is a human oncoprotein that is overexpressed in multiple kinds of cancers including non-small cell lung cancer(NSCLC). CIP2A plays an ’oncogenic nexus’ to participate in the tumorigenesis and chemoresistance in several cancer types. AKT and m TORC1 overactivation are detected in NSCLC and many other cancers. Previous studies found that the CIP2A/AKT/m TOR pathway controls cell growth, apoptosis, autophagy process. Polyphyllin I(PPI) and polyphyllin VII(PPVII) are natural components extracted from Paris polyphylla that display anti-cancer properties. In the present study, we investigated whether PPI and PPVII can be used in the cisplatin(DDP)-resistant human NSCLC cell line A549/DDP. Results demonstrated that PPI and PPVII treatment significantly suppressed A549/DDP cell proliferation, migration, invasion and EMT, induced apoptosis and autophagy. Further examination of the mechanism revealed that the PPI and PPVII significantly upregulated the p53, induced caspase-dependent apoptosis and suppressed the CIP2A/AKT/m TOR pathway. The activation of autophagy was mediated through PPI and PPVII induced inhibition of m TOR. We propose that PPI and PPVII might be developed as candidate drugs for DDP-resistant NSCLC.

关键词： Polyphyllin I Polyphyllin VII Cisplatin-resistance Non-small cell lung cancer p53 Cancerous inhibitor of protein phosphatase 2A

基于哨兵函数和S变换的风力机叶片材料损伤特性研究

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太阳能学报 2024年第7期45卷 656-663页

作者：廖力达舒王咏张芝铭刘亮冯飞陈为强长沙理工大学能源与动力工程学院长沙410114 通道子舞风能开发有限公司怀化418500

利用声发射检测技术研究玻璃纤维增强环氧树脂复合材料的损伤特性,在此过程中,采用哨兵函数来表征该材料的损伤程度,并通过S变换和模糊C均值(FCM)聚类来分析声发射信号,从而获得材料的损伤特征。三点弯曲实验结束后对试件断口进行扫描... 详细信息

利用声发射检测技术研究玻璃纤维增强环氧树脂复合材料的损伤特性,在此过程中,采用哨兵函数来表征该材料的损伤程度,并通过S变换和模糊C均值(FCM)聚类来分析声发射信号,从而获得材料的损伤特征。三点弯曲实验结束后对试件断口进行扫描电子显微镜(SEM)拍照来验证,可得:通过对SEM照片的分析得到基体开裂、纤维脱粘、分层破坏、纤维断裂4种损伤模式;对整个声发射事件进行哨兵函数分析,观察到试件在弯曲过程中哨兵函数曲线呈明显下降趋势;对依据哨兵函数划分的不同阶段的信号进行VMD降噪处理,然后采用S变换进行时频分析得到不同损伤的特征频率,最后采用FCM聚类进行验证。结果表明:哨兵函数值的突变可作为材料断裂的预警信号,材料损伤类型的识别可依据S变换的频率分布结果进行确定。

关键词：风力机叶片复合材料声发射损伤特性哨兵函数 S变换

同方期刊数据库博看期刊评论

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对照提取物在人参配方颗粒质量分析中的应用

中药新药与临床药理 2024年第5期35卷 725-729页

作者：陈海燕吴垠陈静娴巫少娟张奕尧冯飞刘飞高双郭隆钢广州科曼生物科技有限公司广东广州510663 安徽科耘百草医药有限公司安徽亳州236800

目的以人参水提对照提取物(GWERS)为参照,对11个不同厂家的19批人参配方颗粒进行质量分析。方法根据国家药品监督管理局颁布的人参配方颗粒标准(YBZ-PFKL-2021186)鉴别和特征图谱方法进行薄层色谱(TLC)鉴别,以及特征图检测。结果TLC分... 详细信息

目的以人参水提对照提取物(GWERS)为参照,对11个不同厂家的19批人参配方颗粒进行质量分析。方法根据国家药品监督管理局颁布的人参配方颗粒标准(YBZ-PFKL-2021186)鉴别和特征图谱方法进行薄层色谱(TLC)鉴别,以及特征图检测。结果TLC分析结果表明,19批人参配方颗粒样品可以分成3类,第1类样品整体图谱与GWERS一致,相似度高;第2类样品检出西洋参特有成分伪人参皂苷F11;第3类样品图谱比GWERS多4个蓝色荧光斑点。HPLC分析结果表明,19批人参配方颗粒均呈现与GWERS色谱中保留时间相对应的8个特征峰。其中一厂家的3批样品图谱比其他样品图谱多出两个色谱峰,与GWERS图谱相似度低于0.65,其余16批样品图谱与GWERS图谱相似度高于0.94。结论目前市售的人参配方颗粒质量差异较大,疑存在混有西洋参投料的情况。应用GWERS分析人参配方颗粒的质量比对照药材具有更好的适用性。

关键词：人参配方颗粒对照提取物薄层色谱高效液相色谱质量分析

Simultaneous realization of direct photodeposition and high H_(2)-production activity of amorphous cobalt sulfide nanodot-modified rGO/TiO_(2)photocatalyst

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Rare Metals 2021年第11期40卷 3125-3134页

作者： feng Chen Hong-fei feng Wei Luo Ping Wang Huo-Gen Yu Jia-Jie Fan School of Chemistry Chemical Engineering and Life SciencesWuhan University of TechnologyWuhan 430070China State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450002China

To realize highly efficient hydrogen production of graphene-based photocatalysts,it is greatly important to increase more interfacial active sites onto *** this work,the highly efficient CoS_(x)-rGO(reduced graphene oxide)/TiO_(2) composite photocatalyst was synthesized via a simple two-step method,including the hydrothermal loading of rGO nanosheets onto TiO_(2) nanoparticles and the subsequent photodeposition process of CoS_(x) nanodots(0.5-2 nm) on the rGO *** experimental results confirmed that the CoS_(x)-rGO/TiO_(2) photocatalyst displayed a distinctly higher photocatalytic H_(2)-evolution activity than the TiO_(2) *** highest hydrogen-production efficiency of obtained CoS_(x)-rGO/TiO_(2)(10%) achieved 256.97 μmol·h-1,which was distinctly higher than that of TiO_(2)(4.41 μmol·h-1),rGO/TiO_(2)(20.19 μmol·h^(-1)) and CoS_(x)/TiO_(2)(132.67 μmol·h^(-1)).According to the results of various characterizations and tests,the synergistic-effect mechanism of CoS_(x) nanodots and rGO nanosheets is proposed to explain the increased photocatalytic performance of Co S_(x)-rGO/TiO_(2) photocatalytic material,namely the rGO nanosheets cause the quick transfer of photo-induced carriers from TiO_(2) to CoS_(x) nanodots,and then CoS_(x) nanodots work as hydrogenproduction active sites to quickly generate H_(2).The present study may offer innovative ideas for the preparation and application of new highly efficient and inexpensive photocatalytic materials.

关键词： Photocatalysis Hydrogen evolution Titania Cobalt sulphide Direct photodeposition