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A Description of Fixed Subgroups of Free Groups

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Chinese Annals of Mathematics,Series B 2016年第5期37卷 713-718页

作者： qiang zhang School of Mathematics and Statistics Xi’an Jiaotong University

Let F be a finitely generated free group. Martino and Ventura gave an explicit description for the fixed subgroups of automorphisms of F. The author generalizes their results to injective endomorphisms.

关键词： subgroups Fixed finitely automorphism explicit trivial isomorphic invariant integers argument

Risk assessment of erosive aggressiveness due to the condensation shock by numerical simulation

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Journal of Hydrodynamics 2022年第2期34卷 200-206页

作者： Wei zhang bing Zhu Science and Technology on Water Jet Propulsion Laboratory Marine Design and Research Institute of ChinaShanghai200011China School of Energy and Power Engineering University of Shanghai for Science and TechnologyShanghai200093China

Cavitation is,for the engineering areas such as fluid machinery and ship propulsion,a known source of *** erosion damage due to cavitation bubble collapse can lead to extreme failure events,implying the replacement of a ship propeller or a turbine in a hydropower plant,all of which are very costly *** dynamics of cavitation hydraulic structure is of great importance for cavitation *** a result,the blade surface endures some extremely high stresses,which lead to the cause of *** major mechanisms,re-entrant jet as well as condensation shock,are known to such transient cavitating *** the present work we study the latter since less has been reported for the erosion caused by such an unsteady cavitating *** adopted an energy transportation equation based method,combined with a collapse event detection strategy,to carry out numerical erosion risk assessment for erosive aggressiveness due to the condensation *** with the paint test,our result shows good agreement in the erosive *** further discussed the hydrodynamics of the related flow structures.

关键词： Condensation shock numerical simulation cavitation erosion

Laser-induced Fluorescence Spectroscopy of CoS： Identification of a New Excited State Arising from the Ground State

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Chinese Journal of Chemical Physics 2013年第6期26卷 701-704,I0004页

作者： Jian-zheng Zang Qun zhang De-ping zhang Cheng-bing Qin qiang zhang Yang Chen Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemical PhysicsUniversity of Science and Technology of China Hefei 230026 China

Laser-induced fluorescence excitation spectra and dispersed fluorescence spectra of cobalt sulfide （COS） have been recorded in the energy range of 22400-24400 cm-1 （corresponding to 446-409 nm）. A new electronic transition progression with six vibronic bands, stemming from the X4AT/2 state of CoS, was identified and assigned to be [24.0014AT/2-X4A7/2. The new observed 4A state most probably originates from the core[10a2][47r3][lla2][153][57r3] electronic configuration. Strong perturbations are found to extensively exist in the transition bands of this new state. The rotational constants and lifetimes of these bands have been determined.

关键词： CoS Laser-induced fluorescence Dispersed fluorescence Perturbation amongstates

■Ω and ■^(*)Ω Dibaryons in SC7(3)Chiral Quark Model

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Chinese Physics Letters 2000年第3期17卷 182-184页

作者： LI qiang-bing SHEN Peng-Nian Institute of High Energy Physics Chinese Academy of ScienceBeijing 100039 Chinese Center of Advanced Science and Technology(World Laboratory) Beijing 100080 Institute of Theoretical Physics Chinese Acedemy of SciencesBeijing 100080 Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion AcceleratorLanzhou 730000

The binding energy of the six quark system with strangeness s=-5 is investigated by the SU(3)chiral constituent quark *** single ■^(*)Ω channel calculation with spin S=Q and the coupled ■Ω-■^(*)Ω channel calculation with spin S=1 are *** is shown that in the spin S=0 case,the binding energy of ■^(*)Ω is ranged from 80.0 to 92.4MeV,while in the S=1 case,the additional ■^(*)Ω channel increases the binding energy of ■Ω to a range of 26.2-32.9 MgV.

关键词： model quark S=1

Design of an energetic particle radiation diagnostic spectroscopy system based on national core chips and Qt on Linux in EAST

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Nuclear Science and Techniques 2021年第7期32卷 11-21页

作者： Ying-Ying Zheng Zi-Han zhang qiang Li Hong-Rui Cao Yong-qiang zhang Jin-Long Zhao Qi-Ping Yuan bing-Jia Xiao Ling-Ling Yan Jian-Qiu Zhu Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China Hefei University of Technology Hefei 230009China

Energetic particle radiation diagnoses mainly detect the particles(such as neutrons,gamma rays,hard X-rays,and escaping electrons)that are radiated in the discharge process of the experimental advanced superconducting tokamak device to characterize the operating state of the plasma in real *** upgrading of these diagnoses requires new instruments based on national(here,“national”means developed and produced by a Chinese company)core chips and open-source software with advanced digitization,a high sampling rate,and a high time *** new spectroscopy system designed in this study adopts the national field-programmable gate array(FPGA)and an analog-to-digital converter as the core chip,and it is developed using Qt on *** communication between the FPGA and embedded controller occurs via a high-speed peripheral component interconnect eXtension for instrument express protocol with a direct memory access *** this basis,the time resolution of the system is improved from 2 to 1 ms,the maximum channel address is increased to 4096,and the sampling rate is increased from 10 to 80 *** experiments of the spectroscopy system with 152Eu and 137Cs sources demonstrate that the best energy resolution is 0.27%and the measurement error is less than±0.5 keV.

关键词： Spectroscopy system National chip Qt Energetic particle radiation Experimental advanced superconducting tokamak

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退变性脊柱侧凸主弯区的退变程度分析

中国组织工程研究 2025年第15期29卷 3206-3214页

作者：王明朗蒋琳宋彬张力张强冯大雄资阳市雁江区人民医院脊柱外科四川省资阳市641300 西南医科大学附属医院脊柱外科四川省泸州市646000

背景:退变性脊柱侧凸的发病机制不清,主弯区非对称退变可能与侧凸发生、发展紧密相关,充分认识主弯区的退变有助于为临床治疗策略提供更多参考。目的:探讨退变性脊柱侧凸主弯区退变程度与脊柱骨盆参数之间的关系,了解其发病机制。方法:... 详细信息

背景:退变性脊柱侧凸的发病机制不清,主弯区非对称退变可能与侧凸发生、发展紧密相关,充分认识主弯区的退变有助于为临床治疗策略提供更多参考。目的:探讨退变性脊柱侧凸主弯区退变程度与脊柱骨盆参数之间的关系,了解其发病机制。方法:收集西南医科大学附属医院脊柱外科2018年7月至2023年11月就诊的退变性脊柱侧凸患者的病历及影像学资料。比较顶椎上、下关节突关节凹侧、凸侧关节炎的差异;分析脊柱侧凸严重程度、脊柱骨盆参数、关节突关节炎等参数之间的相关性;探究脊柱侧凸严重程度、脊柱骨盆参数、关节突关节炎等参数之间的影响作用。结果与结论:①在顶椎关节突关节中,凹侧比凸侧关节突关节炎严重,差异有显著性意义(P<0.001);在顶椎同侧(凹侧或凸侧)上关节突关节炎比下关节突关节炎严重,差异有显著性意义(P<0.001);②骨盆入射角随着腰椎前凸角减小而减小(rs=0.509,P<0.001);顶椎侧方骨赘差值随着腰椎前凸角减小而增加(rs=-0.285,P=0.033);关节突关节不对称角随着骨盆入射角减小而增加(rs=-0.379,P=0.004);③L5倾斜角、椎间盘角度是主弯Cobb角增大的危险因素(B=1.012,P<0.001;B=0.620,P=0.016);骨盆入射角是主弯Cobb角增大的保护因素(B=-0.264,P=0.003);④提示退变性脊柱侧凸顶椎区域凹侧退变程度重于凸侧;顶椎关节突关节不对称角及关节突关节炎严重程度与脊柱侧凸严重程度无明显相关性;腰椎前凸角和骨盆入射角在维持脊柱正常序列中发挥关键作用,且骨盆入射角是主弯Cobb角增大的保护因素;L5倾斜角和椎间盘角度是主弯Cobb角增大的危险因素。

关键词：退变性脊柱侧凸主弯区顶椎不对称退变关节突关节炎

Design of infrared camouflage cloak for underground silos

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Defence Technology（防务技术） 2020年第1期16卷 43-49页

作者： Luo zhang qiang zhang Hong Ye Department of Thermal Science and Energy Engineering University of Science and Technology of ChinaHefei 230027PR China

The temperature difference between the exposed surface of an underground silo and the surrounding soil surface is significant,which means a silo can be easily found by infrared *** designed an infrared camouflage cloak consisting of an imitative layer and an insulation layer for the *** imitative layer is used to imitate the thermal response of the soil to the surrounding *** insulation layer is used to weaken the impact of the internal temperature field of the silo on the lower boundary of the imitative layer.A silo model including surrounding soil and a soil model without silo were established,and the influences of the material and thickness of each layer on the infrared camouflage effect were *** results show that when using a silicone rubber containing alumina powder with a volume fraction of 3.18% as the imitative material,its thermal inertia is in consistent with that of the ***,it was found that the thickness of the imitative layer doesn't need to be greater than its thermal penetration depth to achieve the infrared camouflage,and the absence of the insulation layer will cause hot spots on the silo surface in winter to weaken the camouflage *** optimized thicknesses of the imitative layer and the insulation layer are 22 cm and 4 cm re *** simulations indicate that with the application of the cloak,the maximum value of the absolute values of the temperature differences between the average temperatures of the silo surface and the surrounding soil surface temperatures drops from 1,59℃ to 0.31℃ in summer and from 1.92℃ to 0.21℃ in *** designed cloak can achieve an all-weather and full-time passive infrared camouflage.

关键词： Underground silo Infrared camouflage cloak Imitative layer Insulation layer

Whole-infrared-band camouflage with dual-band radiative heat dissipation

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Light(Science & Applications) 2023年第11期12卷 2391-2401页

作者： bing Qin Yining Zhu Yiwei Zhou Min Qiu qiang Li State Key Laboratory of Modern Optical Instrumentation College of Optical Science and EngineeringZhejiang UniversityHangzhou 310027China Key Laboratory of 3D Micro/Nano Fabrication and Characterization of Zhejiang Province School of EngineeringWestlake University18 Shilongshan RoadHangzhou 310024 ZhejiangChina Institute of Advanced Technology Westlake Institute for Advanced Study18 Shilongshan RoadHangzhou 310024 ZhejiangChina

Advanced multispectral detection technologies have emerged as a significant threat to objects,necessitating the use of multiband ***,achieving effective camouflage and thermal management across the entire infrared spectrum,especially the short-wave infrared(SWIR)band,remains *** paper proposes a multilayer wavelength-selective emitter that achieves effective camouflage across the entire infrared spectrum,including the near-infrared(NIR),SWIR,mid-wave infrared(MWIR),and long-wave infrared(LWIR)bands,as well as the visible(VIS)***,the emitter enables radiative heat dissipation in two non-atmospheric windows(2.5-3μm and 5-8μm).The emitter’s properties are characterized by low emittance of 0.270/0.042/0.218 in the SWIR/MWIR/LWIR bands,and low reflectance of 0.129/0.281 in the VIS/NIR ***,the high emittance of 0.742/0.473 in the two non-atmospheric windows ensures efficient radiative heat dissipation,which results in a temperature decrement of 14.4℃ compared to the Cr reference at 2000Wm^(−2) input power *** work highlights the role of solar radiance in camouflage,and provides a comprehensive guideline for developing multiband camouflage compatible with radiative heat dissipation,from the visible to LWIR.

关键词： dissipation visible radiative

When and How Plate Tectonics Began?

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Journal of Earth Science 2023年第4期34卷 1302-1303页

作者： Shao-bing zhang School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China

Plate tectonics is the most important discovery in Earth Science in the 20th Century and is the core theory of Solid Earth Science. It describes that the Earth’ s lithosphere is divided into several plates that slide on top of the asthenosphere and move relative to each other along divergent, convergent, and transform plate boundaries. From a physical point of view.

关键词： Earth divergent tectonics