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氟处理下茶树根系的组织细胞形态差异及蜡质合成相关基因WSD1的表达分析

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茶叶科学 2024年第2期44卷 219-230页

作者：宋博贾培凝叶文祺吴俊孙威江薛志慧福建农林大学园艺学院福建福州350002 福建农林大学安溪茶学院福建安溪362406 福建省茶产业工程技术研究中心福建福州350002

茶树是一种氟含量较高的植物,具有聚氟性。基于扫描电镜技术,探究不同质量浓度(10 mg·L^(-1)和50 mg·L^(-1))及不同时间(1 d和16 d)氟处理下,氟高富集茶树品种黄棪和氟低富集茶树品种佛手根系吸收富集氟的特性差异,并对前期转录组数... 详细信息

茶树是一种氟含量较高的植物,具有聚氟性。基于扫描电镜技术,探究不同质量浓度(10 mg·L^(-1)和50 mg·L^(-1))及不同时间(1 d和16 d)氟处理下,氟高富集茶树品种黄棪和氟低富集茶树品种佛手根系吸收富集氟的特性差异,并对前期转录组数据筛选出氟处理下茶树蜡质合成的差异基因WSD1进行分析。结果显示,50 mg·L^(-1)氟处理后,黄棪根部表皮细胞表面覆盖的蜡质稍有增多,细胞排列较为疏松,而佛手根部表皮细胞界限模糊,覆盖蜡质明显增多,细胞壁出现扭曲断裂等氟不耐受症状。蜡质合成相关基因WSD1荧光定量结果显示,WSD1经外源氟处理后,其对茶树根部的蜡质有较为明显的上调作用;WSD1蛋白互作网络预测结果及相关性分析显示,WSD1受CSS0041298、CSS0012327及CSS0049082的负调控。本研究从茶树与蜡质合成互作角度探究茶树缓解氟胁迫的响应机制,为深入探究茶树氟吸收调控和耐氟茶树品种的选育提供科学依据。

关键词：茶树氟 SEM 蜡质合成基因

PSO-Fuzzy-PID复合控制器在喉栓调节发动机压强控制中的应用

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推进技术 2024年第7期45卷 269-278页

作者：高潇王庆辉薛智慧刘金国沈阳化工大学信息工程学院辽宁沈阳110412 中国科学院沈阳自动化研究所机器人学国家重点实验室辽宁沈阳110016 中国科学院机器人与智能制造创新研究院辽宁沈阳110169

为了改善喉栓调节发动机的燃烧室内压强控制系统的性能,实现精确闭环控制,建立了系统的数学模型,并在此基础上提出了一种基于粒子群优化(Particle Swarm Optimization,PSO)算法的Fuzzy-PID复合控制器(PSO-Fuzzy-PID)。由于模型具有较强... 详细信息

为了改善喉栓调节发动机的燃烧室内压强控制系统的性能,实现精确闭环控制,建立了系统的数学模型,并在此基础上提出了一种基于粒子群优化(Particle Swarm Optimization,PSO)算法的Fuzzy-PID复合控制器(PSO-Fuzzy-PID)。由于模型具有较强的时变性、扰动性以及非线性,传统的PID控制器无法精确控制,因此设计并使用PSO-Fuzzy-PID复合控制器。Fuzzy控制器和PID控制器同时工作,采用PSO算法对Fuzzy控制器和PID控制器的输出比例因子进行优化。通过仿真对比了PSOFuzzy-PID复合控制器、Fuzzy-PID双模控制器和传统PID控制器在系统的工作点(6 MPa)附近的阶跃跟踪、时变性测试以及在非线性模型中的抗干扰性测试、长时间全压强范围调节测试,来验证控制器的动态性能。结果表明:在不同的实验中,PSO-Fuzzy-PID复合控制器均表现出明显的优势。该控制器可以将超调量控制在10%以内;将调节时间控制在1.5 s以内,将压强的调节速度提高至Fuzzy-PID双模控制器的3.45~6.73倍,传统PID控制器的4.51~7.1倍。因此PSO-Fuzzy-PID复合控制器在响应速度、超调量、鲁棒性强等方面更具优势,显著地提高了喉栓调节发动机的燃烧室内压强控制系统的动态性能。

关键词：喉栓调节发动机复合控制器压强控制非线性控制时变性

Review of in-space assembly technologies

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Chinese Journal of Aeronautics 2021年第11期34卷 21-47页

作者： zhihui xue Jinguo LIU Chenchen WU Yuchuang TONG State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169China University of Chinese Academy of Sciences Beijing 100049China

With the rapid development of space technology and the increasing demand for space missions,the traditional spacecraft manufacturing,deployment and launch methods have been unable to meet existing ***-space assembly(ISA)technologies can effectively adapt to the assembly of large space structures,improve spacecraft performance,and reduce operating *** this paper,the development and technologies for ISA are *** is classified from multiple angles,and the research status of ISA is shown clearly through the visual mapping knowledge *** the development status of autonomous robot assembly in the United States,Europe,Japan,Canada and China is ***,the key technologies of ISA are analyzed from three aspects:assembly structure design,robot technologies and integrated management *** technologies are still facing major challenges and need to be further explored to promote future ***,future development trends and potential applications of ISA are given,which show that ISA will play a vital role in human space exploration in the future.

关键词： In-situ resource utilization In-space assembly Modular On-orbit servicing Space robots

10-Gb/s Transmission in WDM PON Employing Reflective Semiconductor Optical Amplifier and Fibre Bragg Grating Equaliser

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China Communications 2014年第1期11卷 119-125页

作者： ZHANG Zhiguo CAO zhihui CHEN xue WANG Liqian ZHANG Min State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications Beijing 100876 China

We propose a 10-Gb/s Wavelength- Division-Multiplexed Passive Optical Network （WDM-PON） scheme with upstream transmi- ssion employing Reflective Semiconductor Op- tical Amplifier （RSOA） and Fibre Bragg Gra- ting （FBG） optical equaliser. Transmissions of 10-Gb/s non return-to-zero signals using a 1.2- GHz RSOA and FBG optical equaliser with different setups are demonstrated. Significant performance improvement and 40-kin standard single mode fibre transmission are achieved using FBG optical equaliser and Remotely Pum- ped Erbium-Doped Fibre Amplifier （RP-EDFA）, where they are used to equalise the output of the band-limited RSOA and amplify the seed light and upstream signal, respectively.

关键词： optical equalization fibre bragg grating reflective semiconductor optical amp- lifier remotely pumped erbium-doped fibre amplifier wavelength-division-multiplexed pas- sive optical network

Experimental and DFT Investigations of AlNbTiVZr High Entropy Alloys with Excellent Mechanical Properties

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Acta Metallurgica Sinica(English Letters) 2024年第9期37卷 1480-1490页

作者： Hongwei Yan Yong'an Zhang Wei Xiao Boyu xue Rui Liu Xiwu Li zhihui Li Baiqing Xiong State Key Laboratory of Nonferrous Metals and Processes China GRINM Group Co.Ltd.Beijing100088China GRIMAT Engineering Institute Co. Ltd.Beijing101407China General Research Institute for Nonferrous Metals Beijing100088China

This study investigated the microstructure and mechanical properties of AlNbTiVZr series high-entropy alloys(HEAs)through both experimental studies and density functional theory *** improvements in the microstructures and mechanical properties were achieved for the AlNbTiVZr series HEAs by meticulously adjusting the alloy composition and employing homogenization heat ***,the specimen designated as Al_(0.5)NbTiVZr_(0.5) demonstrated excellent mechanical properties including a compressive yield strength of 1162 MPa and a compressive strength of 1783 *** homogenization heat treatment at 1000℃ for 24 h,the Al_(0.5)NbTiVZr_(0.5) alloy exhibits brittle-to-ductile *** atomic-scale theoretical simulations reveal that the decrease of Al content intrinsically enhances the ductility of the alloys,thereby indicating that the mechanical properties of the AlNbTiVZr series HEAs were significantly influenced by the chemical ***,specific atomic pair formations were observed to adversely affect the microstructure of the AlNbTiVZr series HEAs,particularly in terms of *** findings provide valuable insights for the design and optimization of light weight HEAs,emphasizing the synergistic adjustment of alloy composition and heat treatment processes to achieve a balance between the strength and ductility.

关键词： High-entropy alloy Microstructure Mechanical properties Density functional theory

Enhancing dielectric properties and energy storage performance of polyvinylidene fluoride composite by surface-modified AgNbO_(3) nanoparticles

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High Voltage 2024年第4期9卷 939-947页

作者： Zhuo Wang Ting Zhao Dan Wu Ying xue zhihui Yi Jinteng Kang Ronghui Ye Ning Guo Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic Materials School of Materials Science and EngineeringShaanxi University of Science and TechnologyXi'anChina Key Laboratory of Engineering Dielectrics and Its Application Ministry of EducationHarbin University of Science and TechnologyHarbinChina

The introduction of antiferroelectric filler AgNbO_(3) into the polyvinylidene fluoride(PVDF)polymer matrix enhances its energy storage properties of ***,AgNbO_(3) and PVDF matrix are incompatible due to their distinct physical and chemical properties,resulting in poor compatibility between the two *** modification enhances the large difference in physical and chemical properties between the filler and the polymer matrix,and improves the compatibility between the two *** coupling agents(KH550,KH560),dopamine(DA),and grafted poly(methyl methacrylate)(PMMA)were used to modify the surface of AgNbO_(3) particles,and the effects of different surface modification methods on the energy storage performance of the composites were *** PVDF matrix was introduced with 0.3 wt%AgNbO_(3) particle *** results showed that the amino group in KH550 had the strongest binding with *** ester group in PMMA has a strong binding with *** epoxy group in KH560 has a weak binding with PVDF,while the amino group in DA has the worst binding with *** compatibility of the two phases in AgNbO_(3)@KH550/PVDF composites is the best,and the charge distribution on the surface of the filler is *** an electric field of 350 kV/mm,the energy storage density is 8.48 J/cm^(3).

关键词： composites composite filler

DsMTOPVIB Promotes Meiotic DNA Double-Strand Break Formation in Rice

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Molecular Plant 2016年第11期9卷 1535-1538页

作者： zhihui xue Yafei Li LeiZhang Wenqing Shi Chao Zhang Mengshi Feng Fanfan Zhang Ding Tang Hengxiu Yu Minghong Gu Zhukuan Cheng State Key Laboratory of Plant Genomics and Center for Plant Gene Research Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing 100101 China Key Laboratory of Crop Genetics and Physiology of Jiangsu Province/Key Laboratory of Plant Functional Genomics of Ministry of Education Yangzhou University Yangzhou 225009 China These authors contribute equally to this article

Dear Editor,Meiotic recombination is initiated by the generation of DNA double-strand breaks （DSBs）, which are catalyzed by the Spo11 protein （de Massy, 2013）. Two key findings point to the role of Spo11 as the initiator of DSB formation in budding yeast：（1） Spo11 is linked to the 5＇ termini of the broken DNA molecules in rad50s mutants, whose meiosis has been blocked at the stage of the cleavaqe reaction （＇Keenev et al., 1997）.

关键词： DNA双链断裂减数分裂 DNA分子芽殖酵母引发剂 DSB 蛋白突变

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空间机械臂操控技术研究综述

机器人 2022年第1期44卷 107-128页

作者：薛智慧刘金国中国科学院沈阳自动化研究所机器人学国家重点实验室辽宁沈阳110016 中国科学院机器人与智能制造创新研究院辽宁沈阳110169 中国科学院大学北京100049

考虑到空间机械臂在执行在轨维修、在轨组装、在轨加注等复杂危险的空间任务时,其精准、灵巧的操控技术的重要性,从不同类型空间机械臂构形、末端执行器出发,分析了空间机械臂的发展趋势。综述了空间机械臂操控过程中涉及的5项关键技术... 详细信息

考虑到空间机械臂在执行在轨维修、在轨组装、在轨加注等复杂危险的空间任务时,其精准、灵巧的操控技术的重要性,从不同类型空间机械臂构形、末端执行器出发,分析了空间机械臂的发展趋势。综述了空间机械臂操控过程中涉及的5项关键技术,包括:交会对接与捕获技术、自主规划与智能控制技术、传感与感知技术、智能协同与操控技术及系统安全保障技术。最后,就现有的空间机械臂在操控过程中面临的问题,提出未来的发展方向及展望。

关键词：空间机械臂末端执行器在轨服务在轨操作人机交互

中国科学家在杂种F_1克隆繁殖研究领域取得突破性进展

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植物学报 2019年第1期54卷 1-3页

作者：薛治慧种康中国科学院植物研究所植物分子生理学重点实验室北京100093

杂种优势在提高作物产量和适应性方面已得到广泛应用。然而,由于杂交种后代不能稳定遗传,每年均需利用不育系和恢复系亲本配置杂交种子,不仅制种成本高,而且存在制种纯度问题,限制了杂种优势利用的推广范围。近期,中国科学家通过对减数... 详细信息

杂种优势在提高作物产量和适应性方面已得到广泛应用。然而,由于杂交种后代不能稳定遗传,每年均需利用不育系和恢复系亲本配置杂交种子,不仅制种成本高,而且存在制种纯度问题,限制了杂种优势利用的推广范围。近期,中国科学家通过对减数分裂和受精过程关键基因进行编辑,获得了杂种F_1的克隆种子,为进一步固定杂种优势、实现"一系法"水稻杂种优势利用带来了曙光。

关键词：水稻杂种优势无融合生殖减数分裂