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Research progress of space non-pyrotechnic low-shock connection and separation technology(SNLT):A review

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Chinese Journal of Aeronautics 2022年第11期35卷 113-154页

作者： Honghao YUE Yifei YANG Yifan LU Fei YANG Jun wu Qi RUAN zongquan DENG State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 15000lChina

Space missions have become diversified in recent years, where connection and separation devices play a crucial role as key components of various spacecraft. Traditional pyrotechnic devices have the advantages of large carrying capacity, rapid motion and functional reliability. However,their shortcomings such as great release shock, poor safety, unrepeatability and other prominent defects make them unsuitable for new generation spacecraft such as microsatellites to separate at low shock or lock repeatedly, etc. Therefore, it is necessary to develop space non-pyrotechnic low-shock connection and separation devices(SNLD) which are required for advanced aerospace missions. In this paper, the progress of the research on space non-pyrotechnic low-shock connection and separation technology(SNLT) is summarized and reviewed. Proceed from the principle of reducing shock for non-pyrotechnic devices, present studies are classified from the perspective of actuating technology and systematic designing methods. For non-pyrotechnic actuating techniques,according to different driving sources, the separation devices are classified into several main categories: electric, magnetic, gas and thermal actuating devices. The actuation principle and application prospect of separation techniques are introduced and the working process, dimension and mechanical properties of typical devices are compared and evaluated. For the systematic designing method, the common mechanism types of SNLDs are summarized according to the designing concept of reducing shock. Then connection configurations are classified according to the structural forms of connection devices, of which the principles, bearing capacities and general applications are discussed. This paper systematically summarizes the key problems, puts forward the future development trend of SNLT, and points out the breakthrough direction for related scholars.

关键词： Connection Low-shock Non-pyrotechnic Separation Space

Watt Linkage–Based Legged Deployable Landing Mechanism for Reusable Launch Vehicle: Principle, Prototype Design, and Experimental Validation

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Engineering 2023年第1期20卷 120-133页

作者： Haitao Yu Baolin Tian Zhen Yan Haibo Gao Hongjian Zhang Huiqiang wu Yingchao Wang Yuhong Shi zongquan Deng State Key Laboratory of Robotics and Systems Harbin Institute of TechnologyHarbin 150080China Beijing Institute of Aerospace Systems Engineering Beijing 100076China

The reusable launch vehicle (RLV) presents a new avenue for reducing cost of space transportation. The landing mechanism, which provides landing support and impact absorption, is a vital component of the RLV at final stage of recovery. This study proposes a novel legged deployable landing mechanism (LDLM) for RLV. The Watt-II six-bar mechanism is adopted to obtain the preferred configuration via the application of the linkage variation approach. To endow the proposed LDLM with advantages of large landing support region, lightweight, and reasonable linkage internal forces, a multi-objective optimization paradigm is developed. Furthermore, the optimal scale parameters for guiding the LDLM prototype design is obtained numerically using the non-dominated sorting genetic algorithm-II (NSGA-II) evolutionary algorithm. A fully-functional scaled RLV prototype is developed by integrating the gravity-governed deploying scheme to facilitate unfolding action to avoid full-range actuation, a dual-backup locking mechanism to enhance reliability of structure stiffening as fully deployed, and a shock absorber (SA) with multistage honeycomb to offer reliable shock absorbing performance. The experimental results demonstrate that the proposed LDLM is capable of providing rapid and smooth deployment (duration less than 1.5 s) with mild posture disturbance to the cabin (yaw and pitch fluctuations less than 6°). In addition, it provides satisfactory impact attenuation (acceleration peak less than 10g (g is the gravitational acceleration)) in the 0.2 m freefall test, which makes the proposed LDLM a potential alternative for developing future RLV archetype.

关键词： Reusable launch vehicle(RLV) Deployable mechanism Optimization desi gn

Wide range temperature detection with hybrid nanoparticles traced by surface-enhanced Raman scattering

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Science China Chemistry 2014年第3期57卷 417-425页

作者： YIN Jun HE YaGuang LI Wei WU ZongQuan DING YunSheng Key Laboratory of Advanced Functional Materials and Devices Anhui Province Department of Polymer Material and Engineering School of Chemical Engineering Hefei University of Technology

We report on the fabrication of a class of surface-enhanced Raman scattering(SERS)active thermometers,which consists of60 nm gold nanoparticles,encoded with Raman-active dyes,and a layer of thermoresponsive poly(N-isopropylacrylamide)(PNIPAM)brush with different chain lengths.These SERS-active nanoparticles can be optimized to maintain spectrally silent when staying as single particles in dispersion.Increasing temperature in a wide range from 25 to 55°C can reversibly induce the interparticle self-aggregation and turn on the SERS fingerprint signals with up to 58-fold of enhancement by taking advantage of the interparticle plasmonic coupling generated in the process of thermo-induced nanoparticles self-aggregation.Moreover,the most significative point is that these SERS probes could maintain their response to temperature and present all fingerprint signals in the presence of a colored complex.However,the UV-Vis spectra can distinguish the differences faintly and the solution color shows little change in such complex mixture.This proof-of-concept and Raman technique applied here allow for dynamic SERS platform for onsite temperature detection in a wide temperature range and offer unique advantages over other detection schemes.

关键词：表面增强拉曼散射温度检测金纳米粒子宽范围混合物聚(N-异丙基丙烯酰胺) SERS活性表面等离子体激元

钯配合物催化的环丙烯活性/可控烯基加成聚合

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有机化学 2021年第12期41卷 4830-4831页

作者：侯小华吴宗铨合肥工业大学化学与化工学院先进催化材料与反应工程安徽重点实验室合肥230009

环丙烯是最小的不饱和碳氢环状化合物,由于其超高的环张力(227.7kJ/mol),具有丰富的反应性[1],在有机合成和高分子合成中应用广泛,尤其是其制备出的高分子聚合物具有特殊的骨架结构.但该方向的研究主要聚焦于环丙烯单体发生开环易位聚合... 详细信息

环丙烯是最小的不饱和碳氢环状化合物,由于其超高的环张力(227.7kJ/mol),具有丰富的反应性[1],在有机合成和高分子合成中应用广泛,尤其是其制备出的高分子聚合物具有特殊的骨架结构.但该方向的研究主要聚焦于环丙烯单体发生开环易位聚合(ROMP)得到柔性的不饱和碳链[2].通过环丙烯烯基双键的加成聚合来制备出饱和环状骨架结构的聚合物链则鲜有报道[3].

关键词：开环易位聚合高分子合成环状化合物加成聚合聚合物链高分子聚合物烯基钯配合物

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手性螺旋聚合物的合成和结构控制

有机化学 2023年第12期43卷 4141-4146页

作者：王倩刘雨奇吴宗铨皖西学院材料与化工学院安徽六安237012 吉林大学化学学院超分子结构与材料国家重点实验室长春130012

随着近些年研究的投入,越来越多的手性螺旋聚合物被合成出来并应用于手性分离和光电材料等领域,螺旋聚合物根据螺旋翻转壁垒的大小可以分为静态螺旋聚合物和动态螺旋聚合物.主要聚焦于手性聚异氰酸酯、手性聚异腈和手性聚乙炔三类手性... 详细信息

随着近些年研究的投入,越来越多的手性螺旋聚合物被合成出来并应用于手性分离和光电材料等领域,螺旋聚合物根据螺旋翻转壁垒的大小可以分为静态螺旋聚合物和动态螺旋聚合物.主要聚焦于手性聚异氰酸酯、手性聚异腈和手性聚乙炔三类手性螺旋聚合物的合成和结构控制,介绍手性单体聚合、螺旋选择性聚合、手性诱导和手性放大等几种手性螺旋聚合物的合成方法,同时也介绍了构象调控、聚合诱导自组装等光学活性螺旋聚合物的合成方法.

关键词：光学活性螺旋聚合物手性单体聚合螺旋选择性聚合手性诱导手性放大

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重庆市万州区山羊规模养殖疫病防控

饲料博览 2014年第12期24卷 47-49页

作者：吴宗权重庆市万州区动物卫生监督所重庆404120

文章以重庆市万州区为例,总结南方农区肉用山羊规模养殖疫病发生情况、发病特点及其与环境的关系,并提出综合防控措施,以期提高养殖效益。

关键词：肉用山羊规模养殖疫病防控

H型高血压患者血压变异性、红细胞分布宽度对早期肾功能损伤的预测价值分析

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中国循证心血管医学杂志 2023年第9期15卷 1133-1135,1137页

作者：吴贻红张豪赵宗权苏州市立医院全科医学科苏州215000 苏州市立医院心内科苏州215000

目的探讨H型高血压患者血压变异性、红细胞分布宽度(RDW)对早期肾功能损伤的预测价值。方法选择2021年3月至2023年3月于苏州市立医院就诊的100例H型高血压患者为研究对象,根据是否发生早期肾损伤组分为肾损伤组(n=36)和非肾损伤组(n=64)... 详细信息

目的探讨H型高血压患者血压变异性、红细胞分布宽度(RDW)对早期肾功能损伤的预测价值。方法选择2021年3月至2023年3月于苏州市立医院就诊的100例H型高血压患者为研究对象,根据是否发生早期肾损伤组分为肾损伤组(n=36)和非肾损伤组(n=64),比较两组肾功能指标、24h收缩压变异性(24h SBPV)、24h舒张压变异性(24h DBPV)、RDW,分析血压变异性、RDW与肾功能指标的相关性以及对早期肾损伤的预测价值。结果肾损伤组胱抑素C(CysC)、尿微量白蛋白/肌酐比值(UACR),均明显高于非肾损伤组,差异有统计学意义(P<0.05);肾损伤组24h SBPV、24h DBPV、RDW水平均高于非肾损伤组,差异有统计学意义(P<0.05)。经Pearson相关性分析显示,24h SBPV、24h DBPV、RDW和CysC、UACR均呈正相关(P<0.05);受试者工作曲线(ROC)分析显示,24h SBPV预测早期肾损伤的曲线下面积(AUC)为0.934,95%CI:0.883~0.985,24h DBPV的AUC为0.933,95%CI:0.882~0.985,RDW的AUC为0.973,95%CI:0.936~1.000。结论H型高血压合并早期肾损伤患者24hSBPV、24hDBPV、RDW均明显升高,且各指标均对早期肾损伤具有较好的预测价值。

关键词： H型高血压同型半胱氨酸血压变异性红细胞分布宽度肾损伤

Halogen effects on phenylethynyl palladium(Ⅱ) complexes for living polymerization of isocyanides: a combined experimental and computational investigation

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Science China Chemistry 2019年第4期62卷 491-499页

作者： Yaqi Wang Yu Chen Zhiqiang Jiang Fang Liu1 Fang Liu2 Yuanyuan Zhu Yong Liang zongquan wu Department of Polymer Science and Engineering School of Chemistry and Chemical EngineeringAnhui Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei University of TechnologyHefei 230009China State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Phenylethynyl palladium(Ⅱ) complexes have proven to be effective catalysts for coordination polymerization of isocyanides. In this work, two new phenylethynyl palladium(Ⅱ) initiators bearing bromide(1b) and iodide(1c) were synthesized and applied for living polymerization of aryl and alkyl isocyanides. The coordinated halogen anions can significantly influence the kinetics of polymerization, with the observed order of reaction rates being 1c(Ⅰ)>1 b(Br)>1a(Cl). Impressively, 1c not only accelerates the reaction rate in both the initiation stage and propagation stage, but also can polymerize less active monomers that cannot be reacted by 1a. DFT calculations were then employed to understand the detailed mechanism and the halogen effects in this insertion polymerization process.

关键词： polyisocyanide halogen effect living polymerization palladium complex DFT calculation

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压电圆环结构动刚度控制有限差分仿真分析

机械工程学报 2018年第18期54卷 115-122页

作者：王雷邓宗全武练梅汪豪蒂哈尔滨工业大学船舶与海洋工程学院威海264209 哈尔滨工业大学机电工程学院哈尔滨150001 北京电子工程总体研究所北京100085

薄壁飞行器结构在高超音速飞行过程中需要对局部环状区域进行刚度增强。对于层合了压电传感与控制器的圆环刚度控制系统,提出了一种圆环多模态智能结构单元混合程序仿真模型,可以对独立模态进行闭环刚度控制。利用有限差分法,将压电圆... 详细信息

薄壁飞行器结构在高超音速飞行过程中需要对局部环状区域进行刚度增强。对于层合了压电传感与控制器的圆环刚度控制系统,提出了一种圆环多模态智能结构单元混合程序仿真模型,可以对独立模态进行闭环刚度控制。利用有限差分法,将压电圆环动力学偏微分方程转化为含有压电传感与控制效应矩阵的智能结构单元数学矩阵模型;为了解决大矩阵运算和多次循环迭代的问题,建立基于C++/MATLAB混合编程的智能结构单元仿真系统;采用余弦状传感/作动器贴片,对独立模态的位移/加速度反馈动刚度控制进行算例分析,就不同差分密度、积分时间步长和增益比例系数等条件下进行频域与时域仿真分析,取得了较为满意的结果。该方法为复杂回转曲面结构的智能结构系统的大数据量离散化仿真分析提供了新的解决方案。

关键词：压电圆环混合程序仿真有限差分离散化模型刚度控制