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测地激光陀螺仪的倾斜角误差分析

光电子．激光 2024年第5期35卷 544-551页

作者：武威郭文阁江兴涛杨哲高玉平张首刚西安石油大学电子工程学院陕西西安710065 中国科学院国家授时中心时间频率基准重点实验室陕西西安710600 西安石油大学理学院陕西西安710065

测地激光陀螺仪是测量地球自转角速度的重要工具,为世界时(universal time,UT1)解算提供依据。环境变化会影响测地激光陀螺仪光学腔的几何形状,从而影响陀螺仪的测量精度。本文主要针对由测地激光陀螺仪平面倾斜带来的陀螺仪萨格奈克(Sa... 详细信息

测地激光陀螺仪是测量地球自转角速度的重要工具,为世界时(universal time,UT1)解算提供依据。环境变化会影响测地激光陀螺仪光学腔的几何形状,从而影响陀螺仪的测量精度。本文主要针对由测地激光陀螺仪平面倾斜带来的陀螺仪萨格奈克(Sagnac)频差之误差进行研究,结合基本误差理论、坐标系理论,推导出倾斜对陀螺仪旋转角速度影响的理论模型;利用艾伦方差法(Allan deviation,AD)分析3个实验室的倾斜数据,并根据分析结果对原始数据作去噪处理;在此基础上使用时间序列法建立倾斜误差补偿模型,将倾斜造成的角速度误差降低一个量级,使输出的Sagnac频差更接近理论值。表明通过构建合理的倾斜误差补偿模型,可以改善陀螺仪输出数据的噪声水平,为陀螺仪进一步优化运行环境及相关数据的处理方法提供参考。

关键词：测地激光陀螺仪误差分析艾伦方差倾斜角时间序列法

Frequency steering of spaceborne clocks based on XPNAV-1 observations

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Chinese Journal of Aeronautics 2023年第6期36卷 266-278页

作者： Mengna HAN Minglei TONG Liansheng LI Yongqiang SHI Tinggao YANG yuping gao National Time Service Center Chinese Academy of SciencesXi'an 710600China Schoolof Astronomy and Space Science University of Chinese Academy of SciencesBejing 100049China Beijing Institute of Control Engineering Beijing 100190China

Due to high stable rotations, timing of pulsars provides a natural tool to correct the frequency deviation of spaceborne atomic clocks. Based on processing the observational data about a year of Crab pulsar given by XPNAV-1 satellite, we study the possibility of correcting the frequency deviation of spaceborne atomic clocks using pulsar timing. According to the observational data in X-ray band and the timing model parameters from radio observations, the pre-fit timing residuals with a level of 67.66 μs are obtained. By fitting the slope of the timing residuals affected by the faked frequency-biased reference clock, we estimated successfully the relative frequency deviation of the reference clock. For a satellite clock with frequency deviation of the order about 10^(-12), a calibration accuracy with relative error of about 2% can be obtained from the Crab pulsar’s data for one *** stability of the time scale based on Crab pulsar is about 10^(-12) for an interval of one year.

关键词： Pulsar time scale Pulsar timing Atomic clock Frequency steering X-ray observation

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青红杨梅果实生物力学特性研究

广东蚕业 2024年第5期58卷 18-20,92页

作者：廖鹏高玉萍王瑶崔飞龙赵宇瑛浙江农业商贸职业学院浙江绍兴312088

为探究青红杨梅的生物力学特性,进一步降低清选分级过程中的损耗,文章以湖南娄底青红杨梅为研究对象,测量并分析了杨梅果实的基本物理特性参数,利用质构仪对杨梅果实进行了压缩力学特性试验。结果显示:青红杨梅果实的外径分布集中在20~2... 详细信息

为探究青红杨梅的生物力学特性,进一步降低清选分级过程中的损耗,文章以湖南娄底青红杨梅为研究对象,测量并分析了杨梅果实的基本物理特性参数,利用质构仪对杨梅果实进行了压缩力学特性试验。结果显示:青红杨梅果实的外径分布集中在20~26 mm范围内,质量分布集中在4~10 g范围内;含水率与外径、质量都不相关,均值约为82.57%;静摩擦系数约为0.19。青红杨梅果实的破裂力为44.38 N,破裂变形量为8.11 mm,破裂形式决定了杨梅分级运储时应当避免碰撞和持续性单载荷挤压。

关键词：青红杨梅物理特性压缩力学特性

Strain-enhanced polarization sensitivity inβ-Ga_(2)O_(3)photodetector

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 126-137页

作者： Yonghui Zhang Huili Liang Fei Xing Qiqian gao Yu Feng yuping Sun Zengxia Mei School of Physics and Optoelectronic Engineering Shandong University of TechnologyZibo 255000China Songshan Lake Materials Laboratory Dongguan 523808China Institute of Physics Chinese Academy of SciencesBeijing 100190China

Polarization-sensitive photodetection and imaging have great application value in fields such as polarization division multiplexing optical communication,remote sensing,near-field imaging and military *** a high polarization ratio has always been the research hotspot in polarization-sensitive *** this paper,we report a compression strain enhanced polarization ratio inβ-gallium oxide(β-Ga_(2)O_(3))single crystal flake.A rigorous crystallographic analysis confirmed its high crystalline quality and ***-resolved polarization Raman spectroscopy(ARPRS)was adopted to study the anisotropy of its optical *** ARPRS measurements and theoretical calculation consistently demonstrate the strong optical anisotropy in the high-qualityβ-Ga_(2)O_(3)flake.A polarization ratio of 0.96 was obtained in the flatβ-Ga_(2)O_(3)***,mechanical strain of±0.7%was introduced intoβ-Ga_(2)O_(3).An increased polarization ratio of 0.98 was achieved in the case of 0.7%compression strain,which is,to the best of our knowledge,the highest value for UVC polarization-sensitive *** corresponds to an improved polarization rejection ratio of *** work proposed a new path towards improving polarization sensitivity by applying strain engineering in the active material.

关键词： gallium oxide polarization photodetector anisotropy strain

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水利工程供水价格常态化调整机制探索

水利发展研究 2024年第1期24卷 66-69页

作者：杨柠李淼郭悦姚玉琴高玉屏刘品王小娜水利部发展研究中心北京100038 水利部水利水电规划设计总院北京100120 水利部宣传教育中心北京100038

为纠正水利工程供水成本长期大幅偏离价格,激励水利工程单位主动强化成本管理,需要建立水利工程供水价格常态化调整机制。水价调整既要考虑外围价格环境的传导作用引起的成本刚性增长,也要考虑供水服务质量和管理单位成本控制因素,构建... 详细信息

为纠正水利工程供水成本长期大幅偏离价格,激励水利工程单位主动强化成本管理,需要建立水利工程供水价格常态化调整机制。水价调整既要考虑外围价格环境的传导作用引起的成本刚性增长,也要考虑供水服务质量和管理单位成本控制因素,构建水利工程供水价格与生产管理要素价格的联动机制。

关键词：供水价格调整要素调整模型调整机制

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J0613-0200驾驭铯钟的方法

航空学报 2023年第3期44卷 210-217页

作者：李变屈俐俐高玉平中国科学院国家授时中心西安710600 中国科学院时间频率基准重点实验室西安710600 中国科学院大学北京100049

近年来随着脉冲星观测设备性能提升,尤其是中国FAST的投入运行,毫秒脉冲星的计时观测精度不断提高,观测资料的数量、质量及时效性也显著改善,为脉冲星时的建立及应用提供有力的数据及技术支持。脉冲星时与原子时具有优势互补的特点,利... 详细信息

近年来随着脉冲星观测设备性能提升,尤其是中国FAST的投入运行,毫秒脉冲星的计时观测精度不断提高,观测资料的数量、质量及时效性也显著改善,为脉冲星时的建立及应用提供有力的数据及技术支持。脉冲星时与原子时具有优势互补的特点,利用中国科学院国家授时中心的铯钟和相关时频设备,结合IPTA dr2数据资料,建立脉冲星驾驭铯钟的实验系统。并以J0613-0200为参考,开展单颗毫秒脉冲星驾驭铯钟的研究。截止目前,实验结果符合单颗毫秒脉冲星驾驭铯钟的预期,证明了脉冲星驾驭原子钟的可行性,并且实验系统建立的综合时间尺度保持了铯钟稳定度的优势。

关键词：毫秒脉冲星铯钟驾驭计时噪声稳定度

Inherent thermal-responsive strategies for safe lithium batteries

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Journal of Energy Chemistry 2024年第2期89卷 519-534,I0012页

作者： Jia-Xin Guo Chang gao He Liu Feng Jiang Zaichun Liu Tao Wang Yuan Ma Yiren Zhong Jiarui He Zhi Zhu yuping Wu Xin-Bing Cheng School of Energy and Environment Southeast UniversityNanjing 211189JiangsuChina School of Chemistry and Materials Science Nanjing University of Information Science and TechnologyNanjing 210044JiangsuChina

Safe batteries are the basis for next-generation application scenarios such as portable energy storage devices and electric vehicles,which are crucial to achieving carbon ***,separators,and electrodes as main components of lithium batteries strongly affect the occurrence of safety *** materials,which can respond to external stimuli or environmental change,have triggered extensive attentions recently,holding great promise in facilitating safe and smart *** review thoroughly discusses recent advances regarding the construction of high-safety lithium batteries based on internal thermal-responsive strategies,together with the corresponding changes in electrochemical performance under external ***,the existing challenges and outlook for the design of safe batteries are presented,creating valuable insights and proposing directions for the practical implementation of safe lithium batteries.

关键词： Lithium battery Thermal safety Thermal runaway Thermal-responsive

Chromosomal-level genome and metabolome analyses of highly heterozygous allohexaploid Dendrocalamus brandisii elucidate shoot quality and developmental characteristics

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Journal of Integrative Plant Biology 2024年第6期66卷 1087-1105页

作者： Jutang Jiang Zeyu Zhang Yucong Bai Xiaojing Wang yuping Dou Ruiman Geng Chongyang Wu Hangxiao Zhang Cunfu Lu Lianfeng Gu Jian gao Key Laboratory of National Forestry and Grassland Administration Beijing for Bamboo&Rattan Science and TechnologyInstitute of Gene Science and Industrialization for Bamboo and Rattan ResourcesInternational Center for Bamboo and RattanBeijing 100102China College of Forestry Basic Forestry and Proteomics Research CenterFujian Agriculture and Forestry UniversityFuzhou 350002China School of Life Science Peking UniversityBeijing 100871China College of Biological Sciences and Biotechnology Beijing Forestry UniversityBeijing 100083China

Dendrocalamus brandisii(Munro)Kurz is a sympodial bamboo species with inimitable taste and flavorful *** rapid growth and use as high-quality material make this bamboo species highly valued for both food processing and wood ***,genome information for *** is lacking,primarily due to its polyploidy and large genome ***,we assembled a high-quality genome for hexaploid ***,which comprises 70chromosomes with a total size of 2,756 Mb,using long-read Hi Fi ***,we accurately separated the genome into its three constituent *** used Oxford Nanopore Technologies long reads to construct a transcriptomic dataset covering 15 tissues for gene annotation to complement our genome assembly,revealing differential gene expression and post-transcriptional *** integrating metabolome analysis,we unveiled that well-balanced lignin formation,as well as abundant flavonoid and fructose contents,contribute to the superior quality of *** *** genomic,transcriptomic,and metabolomic datasets provided a solid foundation for enhancing bamboo shoot quality and developing efficient gene-editing *** study should facilitate research on *** and enhance its use as a food source and wood material by providing crucial genomic resources.

关键词： bamboo shoots Dendrocalamus brandisii(Munro)Kurz flavonoid genome lignin

Carotenoid isomerase regulates rice tillering and grain productivity by its biosynthesis pathway

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Journal of Integrative Plant Biology 2024年第2期66卷 172-175页

作者： Chaoqing Ding Zhengji Shao yuping Yan Guangheng Zhang Dali Zeng Li Zhu Jiang Hu Zhenyu gao Guojun Dong Qian Qian Deyong Ren State Key Laboratory of Rice Biology and Breeding ChinaNational Rice Research InstituteHangzhou 310006China

Tillers are unique inflorescence-like branches in grasses,and their number determines the panicle number,plant architecture,and yield(Shang et al.,2021).Tiller formation mainly undergoes axillary meristem(AM)initiation and tiller bud outgrowth(Wang et al.,2018;Yan et al.,2023).The rice(Oryza sativa)KNOX gene OSH1 is expressed in AMs,and an osh1 mutant produces fewer tillers(Tanaka et al.,2015).

关键词： sativa Oryza panicle