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A muon high-resolution pseudorange measurement method: Application to muon navigation in confined spaces

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Chinese Journal of Aeronautics 2024年第4期37卷 391-404页

作者： Haoyang LI Chunxi ZHANG Xingming FAN Longjie TIAN Tianqi LI yang PANG yanqiang yang Institute of Optics and Electronics School of Instrumentation Science and Optoelectronics EngineeringBeihang UniversityBeijing 100191China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

Confined spaces such as polar regions, deep earth and deep ocean are crucial navigation scenarios where traditional navigation techniques have difficulty in obtaining external signals for positioning. The cosmic ray muons, which carry the spatial and energetic information, are easy to penetrate these confined spaces. Therefore, the unique muon characteristic provides a new perspective to estimate detector position, which can be considered using in confined spaces *** this paper, a well-developed theory of muon navigation is established by combining a muon pseudorange measurement method. Moreover, an Equivalent Velocity Calculation Model(EVCM)and a Muon Sequence Matching Technology(MSMT) are proposed. The first model corrects flight pseudorange error caused by the relativistic energy loss and the second technology compensates the random error in pseudorange measurement. Further, a series of simulations are performed to analyze the muon events number which can be received by detector in different scenarios with the variations of zenith angle, detector area, varied detector plates gap, and muon flight ***, the simulation results demonstrate that the muon navigation update rate every 10 minutes can reach 5.989 in confined spaces at 100 m, and further pseudorange error analysis indicates that the meter-level positioning accuracy can be acquired. Finally, we construct a muon coincidence measurement scheme and verify that the laws of the muon positioning system for high-energy muons are consistent with the simulation results.

关键词： Muon navigation Cosmic ray muons Muon detection technology Muon transmission technology Pseudorange measurement

HMTA-assisted One-pot Synthesis of Greigite Nano-platelet and Its Magnetic Properties

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Journal of Materials Science & Technology 2015年第9期31卷 895-900页

作者： Tuoquan Liao Wei Wang Yongli Song Xianjie Wang yanqiang yang Xiaoyang Liu Academy of Fundamental and Interdisciplinary Sciences Harbin Institute of Technology Department of Physics Harbin Institute of Technology State Key Lab of Inorganic Synthesis and Preparative Chemistry College of Chemistry Jilin University

A facile one-pot hydrothermal procedure for the synthesis of magnetic greigite was investigated in this work, by using FeSO4, thioacetamide, and a tiny amount of hexamethylenetetramine （HMTA） as starting materials. The HMTA molecule, which acted as a chelating agent and an oxidant, could not only tune the valence fluctuation of iron ions, but also direct the hydrothermal reaction towards the exclusive for- mation of greigite platelets with hundreds of nanometers in lateral size. In the presence of a static magnetic field during this synthesis, the greigite nano-platelets were apt to congregate to form 3D flower-like microspheres. A set of experiments suggested that the ferrous ions were at first partly oxidized by HMTA to form ferric intermediates, i.e., Fe（OH）3 and Fe2O3. Then excessive ferrous ions, along with the solid in- termediates, reacted with sulfide ions, and finally evolved into greigite, Taken into consideration that a similar process occurred in magnetotactic bacteria, our results may give a hint at the design of biomimetic synthesis strategies to produce nanomaterials, especially the magnetosome-like greigite.

关键词： GreigiteNano-plateletHydrothermal synthesisMagnetic materials

Laboratory and pilot scale studies on fast pyrolysis of corn stover

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International Journal of Agricultural and Biological Engineering 2008年第1期1卷 57-63页

作者： Yi Weiming Bai Xueyuan Li Zhihe Wang Lihong Wang Nana yang yanqiang School of Light Industry and Agricultural Engineering Shandong University of TechnologyShandong Research Center of Engineering and Technology for Clean EnergyZibo CityShandong Province255049China

In order to design a hot ceramic ball heated down-flow tuber reactor for the pyrolysis liquefaction of agricultural residues,the devolatilization characteristics of pulverized corn stover were studied in a Laminar Entrained Flow Furnace(LEFF)with the temperature range of 800-950 *** flow characteristics of corn stover particles and ceramic balls in a vertical square tube were measured and analyzed by the techniques of particle image velocimetry(PIV).The devolatilization experiments were carried out in an isothermal manner and the maximum of volatile matter of pulverized corn stover particles was 72.68%with the residence time of 189 ms at 950 *** of the first order Arrhenius equation for describing the pulverized corn stover flash pyrolysis were *** the PIV experiments,the corn stover particle axial velocity were measured at different cross-sections of the tube for different *** the tuber connected with a suction pump,the maximum velocity was about 0.79 m/s,determined by the flow rate of the suction ***,a hot ceramic ball heated down-flow tuber reactor was constructed for pilot *** capacity of the reactor was 110.5 kg/h of corn stover powder and the yield of bio-oil was 41.6%of the feed stock.

关键词： Corn stover pyrolysis bio-oil particle image velocimetry

Discrepancy of the magnetic behaviors and crystalline structure on the Co/FeMn and FeMn/Co interfaces with ultrathin Pt spacer

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Rare Metals 2010年第5期29卷 473-479页

作者： LIU yang,FU yanqiang,JIN Chuan,and FENG Chun Department of Materials Physics and Chemistry,University of Science and Technology Beijing,Beijing 100083,China Department of Materials Physics and Chemistry University of Science and Technology Beijing Beijing China

The exchange coupling at the ferromagnetic/antiferromagnetic （FM/AFM） interface is influenced by both the magnetic structure and the crystalline micro-structure. Co/FeMn/Co thin films with 0.4 nm Pt spacer layer inserted into the Co/FeMn and FeMn/Co interface respectively were deposited by means of magnetron sputtering. The two interfaces upon and beneath the FeMn layer show distinct behaviors before and after the Pt spacer inserted. There is a remarkable shrink of the interracial uncompensated spins within the FeMn bottom interracial monolayers, whereas a relaxation of the pinning strength of the FeMn interfacial spins along the out-of-plane direction occurs at the top in- terface. XRD analysis indicates the Pt layer upon the FeMn layer forms an fcc （002） texture, implying the magnetic discrepancy between the top and bottom FeMn interfaces has crystalline structural origins.

关键词： interfaces exchange coupling exchange bias spacer stress anisotropy lattice match

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弹载大视场星惯组合深度融合导航技术

航空学报 2020年第8期41卷 64-75页

作者：宋凝芳杨艳强北京航空航天大学仪器科学与光电工程学院北京100083

为了降低弹载星惯组合(Stellar-INS)飞行中段对调姿观星的要求,提高星惯组合姿态精度,提出了大视场(LFOV)星惯组合深度融合导航方法。小视场(NFOV)星敏感器输出星矢量为主,大视场星敏感器可同时输出姿态和星矢量信息,分别推导了基于星... 详细信息

为了降低弹载星惯组合(Stellar-INS)飞行中段对调姿观星的要求,提高星惯组合姿态精度,提出了大视场(LFOV)星惯组合深度融合导航方法。小视场(NFOV)星敏感器输出星矢量为主,大视场星敏感器可同时输出姿态和星矢量信息,分别推导了基于星敏感器输出姿态和星矢量信息的观测方程,分析了星矢量和姿态观测方法之间的关联性。建立了包含星惯安装误差、陀螺误差以及初始平台误差角的星惯组合全误差项模型,基于线性卡尔曼滤波给出了深度融合导航方法。开展了数学仿真验证,分析了不同调姿观星路径约束下,大/小视场星惯组合性能差异。结果表明,大视场星惯组合深度融合导航方法不仅可以降低调姿观星约束要求,还可以实现组合姿态性能提升。

关键词：大视场星敏感器星惯组合星惯组合全误差项调姿约束深度融合导航

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陡坡型扇三角洲上一类特殊类型河口坝的研究

中国矿业大学学报 2015年第1期44卷 97-103页

作者：杨延强吴胜和中国石油大学(北京)地球科学学院北京102249 中国石油大学(北京)油气资源与探测国家重点实验室北京102249

在渤海湾盆地南堡凹陷柳赞油田沙三段陡坡型扇三角洲前缘上发现一类特殊类型的河口坝沉积体.通过充分利用研究区密井网的岩心和测井资料,对该种沉积微相类型的沉积特征、空间分布特征、物性分布特征进行研究,并对其成因机制进行分析,认... 详细信息

在渤海湾盆地南堡凹陷柳赞油田沙三段陡坡型扇三角洲前缘上发现一类特殊类型的河口坝沉积体.通过充分利用研究区密井网的岩心和测井资料,对该种沉积微相类型的沉积特征、空间分布特征、物性分布特征进行研究,并对其成因机制进行分析,认为该沉积微相为洪水时期在扇三角洲前缘上产生的异重流沉积.研究结果表明:该沉积微相类型岩性组合在垂向上表现为由多个反正韵律组成的整体向上变粗的反韵律,其为沉积物重力流成因机制的特征较明显;该微相在平面上呈舌状形态,在剖面上呈底平顶凸的透镜状,多期微相砂体主要表现为顺物源方向前积叠置的样式;该微相类型层内储层物性垂向上以复合反正韵律为主,受粒度和泥质含量共同控制,平面上,主体部位物性最好,边缘部位物性逐渐变差.该沉积微相与经典扇三角洲河口坝有重要差别,据其特征可初步命名为"舌状坝".

关键词：扇三角洲异重流沉积微相舌状坝柳赞油田

Inhibition of the cGAS–STING pathway:contributing to the treatment of cerebral ischemia-reperfusion injury

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Neural Regeneration Research 2025年第7期20卷 1900-1918页

作者： Hang yang Yulei Xia Yue Ma Mingtong Gao Shuai Hou Shanshan Xu yanqiang Wang School of Clinical Medicine Shandong Second Medical UniversityWeifangShandong ProvinceChina Department of Emergency The Affiliated Hospital of Weifang Medical UniversityWeifangShandong ProvinceChina Department of Neurology Ⅱ The Affiliated Hospital of Weifang Medical UniversityWeifangShandong ProvinceChina

The cGAS–STING pathway plays an important role in ischemia-reperfusion injury in the heart,liver,brain,and kidney,but its role and mechanisms in cerebral ischemia-reperfusion injury have not been systematically ***,we outline the components of the cGAS–STING pathway and then analyze its role in autophagy,ferroptosis,cellular pyroptosis,disequilibrium of calcium homeostasis,inflammatory responses,disruption of the blood–brain barrier,microglia transformation,and complement system activation following cerebral ischemia-reperfusion *** further analyze the value of cGAS–STING pathway inhibitors in the treatment of cerebral ischemia-reperfusion injury and conclude that the pathway can regulate cerebral ischemia-reperfusion injury through multiple *** of the cGAS–STING pathway may be helpful in the treatment of cerebral ischemia-reperfusion injury.

关键词： calcium homeostasis cellular autophagy cerebral ischemia-reperfusion injury cGAS–STING pathway ferroptosis gut–brain–microbiota axis inflammatory light chain 3 microglial cells Syntaxin-17 protein

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空间用四轴陀螺组合浪涌防护及数据填补方法

系统工程与电子技术 2021年第12期43卷 3652-3657页

作者：戴敏鹏张春熹杨艳强北京航空航天大学仪器科学与光电工程学院北京100191

针对空间用四轴陀螺组合换轴及光源切换时产生浪涌以及数据丢失的问题,提出了一种浪涌防护及数据填补方法。首先,采用双光源方案,设计了浪涌防护电路,降低了上电过程中瞬时大电流对元器件的影响。然后,建立了数据填补机制,用来弥补切换... 详细信息

针对空间用四轴陀螺组合换轴及光源切换时产生浪涌以及数据丢失的问题,提出了一种浪涌防护及数据填补方法。首先,采用双光源方案,设计了浪涌防护电路,降低了上电过程中瞬时大电流对元器件的影响。然后,建立了数据填补机制,用来弥补切换过程中丢失的数据。最后,进行了地面数据填补实验,角速率分别设为0.1745 rad/s和1.745 rad/s,预测的角速率与实际的角速率分别相差不超过0.003 rad/s和0.008 rad/s,相对残差分别为0.0039和0.0012,验证了所提方法的有效性。

关键词：空间应用冗余设计浪涌防护灰色预测

高原大风严寒地区无砟轨道嵌缝材料伤损及修复技术研究

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铁道建筑 2018年第8期58卷 97-100,131页

作者：杨延强任新中国铁路兰州局集团有限公司兰州西工务段甘肃兰州730050 兰州交通大学铁道技术学院甘肃兰州730030

对兰新高速铁路不同区段无砟轨道聚氨酯嵌缝材料伤损情况进行现场调研,分析无砟轨道聚氨酯嵌缝材料伤损类型及发展规律。针对高原大风严寒地区嵌缝材料伤损特点,优选相容性好的有机硅柔性密封嵌缝材料进行现场试验性修补。提出无砟轨道... 详细信息

对兰新高速铁路不同区段无砟轨道聚氨酯嵌缝材料伤损情况进行现场调研,分析无砟轨道聚氨酯嵌缝材料伤损类型及发展规律。针对高原大风严寒地区嵌缝材料伤损特点,优选相容性好的有机硅柔性密封嵌缝材料进行现场试验性修补。提出无砟轨道嵌缝材料表面封面、离缝嵌填和整体更换修复技术,为西北特殊环境下高速铁路无砟轨道嵌缝材料伤损的修补提供技术支撑。

关键词：兰新高铁严寒地区无砟轨道现场试验伤损嵌缝材料修复技术