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Life test research of a high specific impulse Hall thruster HEP-140MF

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Plasma Science and Technology 2020年第9期22卷 139-148页

作者： wei MAO Nan WU Yanlin HU Yan SHEN Zhaopu YAO Xuhui LIU yanming wei Beijing Institute of Control Engineering Beijing 100190People's Republic of China Advanced Space Propulsion Laboratory of BICE Beijing 100190People’s Republic of China Beijing Engineering Research Center of Efficient and Green Aerospace Propulsion Technology Beijing 100190People’s Republic of China

In this study,a high specific impulse Hall thruster,HEP-140 MF,having a high discharge voltage,was used to accelerate *** aimed to obtain a high specific impulse and an acceleration zone moving downstream toward the channel exit to reduce wall sputtering erosion of the walls of the discharge channel,hence ensuring an enhanced *** study the lifetime characteristics of the high specific impulse Hall thruster,a life test was performed on the HEP-140 MF thruster for the first time,and performance parameters,such as thrust,specific impulse,and efficiency,were *** in the performance parameters and evolutions in the surface profiles of the discharge channel wall were *** reasons contributing to these changes during the life test were ***,the accelerated life test method was validated on the HEP-140 MF.

关键词： Hall thruster high specific impulse life test accelerated test

The View of Micropropulsion Technology for China’s Advanced Small Platforms in Deep Space

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Space(Science & Technology) 2022年第1期2022卷 100-108页

作者： yanming wei Hao Yan Xuhui Liu Yang Yu Jinyue Geng Tao Chen Tuoqu Fu Gaoshi Su Yu Hu Daoman Han Advanced Space Propulsion Laboratory Beijing Institute of Control EngineeringBeijing 100090China Beijing Engineering Research Center of Efficient and Green Aerospace Propulsion Technology Beijing 100090China

In this paper,micropropulsion systems are analyzed in conjunction with the various mission requirements of China’s deep space *** a great challenge facing the world,deep space exploration can be enabled only in a few countries with a success rate of around 50%.With the advancement of spacecraft and scientific instruments,it is now feasible to build small and low-cost spacecraft for a variety of deep space *** spacecraft become smaller,there is a need for proper micropropulsion *** of propulsion system selections for deep space exploration are discussed with a focus on products developed by Beijing Institute of Control Engineering(BICE).The requirements for propulsion systems are different in lunar/interplanetary exploration and gravitational wave *** propulsion is selected for fast orbit transfer and electric propulsion for increasing scientific *** gas propulsion and microelectric propulsion are good choices for space-based gravitational wave detection due to the capability of variable thrust output at the micro-Newton *** paper also introduces the sub-1-U micropropulsion modules developed by BICE with satisfactory performance in flight tests,which are promising propulsion systems for small deep space platforms.A small probe with an electric sail propulsion system has been proposed for the future solar system boundary exploration of *** electric sail serves as not only a propellant-free thruster but also a detector probing the properties of the space medium.

关键词： propulsion thrust payload

On a problem of Skiba from the Kourovka Notebook

维普期刊数据库评论

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Science China Mathematics 2004年第1期47卷 96-103页

作者： WANG yanming & wei HuaquanLingnan College and School of Mathematics, Zhongshan University, Guangzhou 510275, China School of Mathematics, Zhongshan University, Guangzhou 510275, China Department of Mathematics, Guangxi Teacher’s College, Nanning 530001, China Lingnan College and School of Mathematics Zhongshan University Guangzhou China School of Mathematics Zhongshan University Guangzhou China Department of Mathematics Guangxi Teacher’s College Nanning China

In this paper, we give a positive answer to a recent open problem of Skiba in Kourovka Notebook without using the odd order theorem and other deep theorems. Some of the techniques are improved.

关键词： supersolvable group c-supple merited subgroup complemented subgroup generalized fitting subgroup saturated formation

Cloning and Functional Analysis of Porcine Cycling A

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Journal of Animal Science and Biotechnology 2011年第1期2卷 1-8页

作者： Li Fan Qinghai Tang yanming Zhang wei Liu Gang Tong College of Veterinary Medicine Northwest A ＆ F University Yangling Shanxi 712100 China

Cyclin A is a key regulator of the cell cycle. Its expression may become disrupted in virusinfected cells, leading to deregulation of the cell cycle and increased cell proliferation. Here, we cloned the porcine cyclin A gene and verified its functionality in swine umbilicus vein endothelial cells （SUVEC）. The human cyclin A gene was used to probe databases to clone the pig cyclin A gene electronically. The identified porcine cDNA contained an open reading frame of 1,299 bp, encoding 432 amino acids, the same length as the human cyclin A protein. The porcine cyclin A gene comprises eight exons on chromosome 8. The sequence of the in silico clone and expression of this novel gene were confirmed in SUVEC by reverse transcription PCR. Western blotting of cell lysates from SUVEC transfected with a cyclin A enhanced green fluorescent protein （EGFP） fusion construct revealed a band at approximately 40 kDa. Confocal microscopy of CycA-EGFP-expressing cells showed that the fusion protein was expressed in the nucleus. Flow cytometry demonstrated that more stably expressing SUVEC-CycA-EGFP were in G1 phase （15% to 20% increase） and fewer were in S phase （18% decrease） compared with control ceils. MTS assays showed that the proliferative activity of SUVEC-Cy- cAG-EGFP was significantly higher than that of the control cells. In conclusion, we have cloned the pig cyclin A gene and demonstrated that its biological function is consistent with cyclin A in other mammali- an species. This provides a foundation for future research on the impact of virus infection on cyclin A.

关键词： cell cycle cyclin A live cell imaging MTS assay swine umbilicus vein endothelial cell

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皮纳卫星编队保持动力学分析

中国空间科学技术 2018年第1期38卷 44-53页

作者：杨博田苗魏延明北京航空航天大学宇航学院北京100191 北京控制工程研究所北京100190

针对皮纳卫星在编队飞行中的控制精度要求已提高到微米甚至纳米级,文章研究了小推力作用下高精度的皮纳卫星编队构型保持问题,在考虑摄动影响下,推导维持编队构型需要的控制力与编队距离、编队空间方位等参数之间的关系,为皮纳卫星编队... 详细信息

针对皮纳卫星在编队飞行中的控制精度要求已提高到微米甚至纳米级,文章研究了小推力作用下高精度的皮纳卫星编队构型保持问题,在考虑摄动影响下,推导维持编队构型需要的控制力与编队距离、编队空间方位等参数之间的关系,为皮纳卫星编队构型的设计提供理论指导;同时基于bang-bang控制理论,使用有限状态机设计了一种高精度的编队控制律。仿真表明,提出的控制方法不但可以使系统快速收敛,同时还能使皮纳卫星编队的星间控制精度达到1μm,与滑模控制律相比较,精度提高近103倍。

关键词：小推力器皮纳卫星编队保持 bang-bang控制混合控制

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微小卫星轨道保持的混合切换控制方法

中国空间科学技术 2018年第4期38卷 20-26页

作者：杨博魏鲍杰魏延明苗峻北京航空航天大学宇航学院北京100191 北京控制工程研究所北京100190

固体微推力器阵列作为一种新型推力装置用于微小卫星轨道保持具有精度高、无燃料泄漏、冲量可调等优点,但是微推力器推力不连续的特点,使得控制系统设计时与以往的连续系统有所不同。为了充分发挥微推力器高精度的特性,采用基于混合系... 详细信息

固体微推力器阵列作为一种新型推力装置用于微小卫星轨道保持具有精度高、无燃料泄漏、冲量可调等优点,但是微推力器推力不连续的特点,使得控制系统设计时与以往的连续系统有所不同。为了充分发挥微推力器高精度的特性,采用基于混合系统的切换控制思想,建立了微推力器混合切换系统控制模型。首先,根据固体微推力器的推力特点推导了卫星离散动力学模型;其次,以李雅普诺夫稳定性定律为基础,设计了混合系统脉冲切换控制律;最后,针对小卫星轨道控制进行了仿真验证。结果表明,基于混合系统建立的控制模型能准确反映微推力器的特点,轨道保持精度能达到0.2m,而且推力器消耗量满足卫星长时间在轨运行要求。

关键词：微小卫星固体微推力器阵列混合切换系统轨道控制

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两栖装甲车履带板胶料摩擦极限智能监测研究

兵器材料科学与工程 2021年第6期44卷 55-59页

作者：潘霞魏艳鸣河南经贸职业学院计算机工程学院河南郑州450018

为研究两栖装甲车持久作战能力,提出其履带板胶料摩擦极限智能监测方法,通过胶料的混炼、热炼及出片等制备装甲车履带板。将履带板组装至两栖装甲车,利用装甲承重轮和履带部分的采集器获取两栖装甲车的载荷和履带温度,将履带数据经装甲... 详细信息

为研究两栖装甲车持久作战能力,提出其履带板胶料摩擦极限智能监测方法,通过胶料的混炼、热炼及出片等制备装甲车履带板。将履带板组装至两栖装甲车,利用装甲承重轮和履带部分的采集器获取两栖装甲车的载荷和履带温度,将履带数据经装甲车顶部的GPS传输器传送至计算机。基于最小二乘法,用计算机拟合计算不同环境温度和路面情况的摩擦因数,在计算结果异常时,计算机自动发送警报,实现履带板胶料摩擦极限的智能监测。结果表明:压力增大,材料性状改变,履带板胶料摩擦因数减小,温度升高,摩擦因数下降;该方法可有效监测履带板胶料摩擦因数,且路面越光滑,履带板胶料摩擦因数越小;该方法可在0.9~1.4 s内及时监测履带板胶料摩擦极限。

关键词：两栖装甲车履带板胶料摩擦极限智能监测拉压传感器

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KrF准分子激光空间相干性测量

光学学报 1999年第8期19卷 1094-1100页

作者：刘建胜刘晶儒魏燕明西北核技术研究所西安710024

设计制作了一套反转剪切干涉仪，测量了ＫｒＦ准分子激光的空间相干性。用这种方法，能够一次测量激光的空间相干度，并且在不用条纹相机的条件下能够实时测量相干度随时间的变化过程。在有注入、无注入锁定及在非稳腔中经过不同... 详细信息

设计制作了一套反转剪切干涉仪，测量了ＫｒＦ准分子激光的空间相干性。用这种方法，能够一次测量激光的空间相干度，并且在不用条纹相机的条件下能够实时测量相干度随时间的变化过程。在有注入、无注入锁定及在非稳腔中经过不同路程条件下对激光的空间相干性进行了测量，并且利用变换矩阵分析了相干度在非稳腔中的传播及其演变过程，

关键词：准分子激光反转剪切干涉仪空间相干性

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Gem小体缺失与肌萎缩侧索硬化症

生命的化学 2015年第6期35卷 768-772页

作者：魏砚明山西中医学院实验管理中心晋中030619

肌萎缩侧索硬化症(ALS)是一种以运动神经元死亡为特征的神经退行性疾病,Gem小体缺失是ALS的细胞特征。研究表明m RNA前体剪接异常与ALS有关。剪接体负责m RNA前体的剪接,而Gem小体参与构成剪接体核心组件的富含尿苷的小核核糖核蛋白(U s... 详细信息

肌萎缩侧索硬化症(ALS)是一种以运动神经元死亡为特征的神经退行性疾病,Gem小体缺失是ALS的细胞特征。研究表明m RNA前体剪接异常与ALS有关。剪接体负责m RNA前体的剪接,而Gem小体参与构成剪接体核心组件的富含尿苷的小核核糖核蛋白(U sn RNP)的生物合成。本文将综述ALS相关肉瘤融合蛋白(FUS)、TAR DNA结合蛋白-43(TDP43)以及铜锌超氧化物歧化酶(SOD1)突变体引起Gem小体缺失的机制,为探索ALS的发病机理和开发新的治疗手段提供启示。

关键词：肌萎缩侧索硬化症肉瘤融合蛋白 TAR DNA结合蛋白-43 铜锌超氧化物歧化酶 Gem小体