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High Temperature Phase Transitions in Na_xCoO_2 Materials

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Chinese Journal of Structural Chemistry 2006年第8期25卷 997-1003页

作者： NIE Chang-jiang YANG Huai-Xin SHI You-Guo li jian-qi Department of Physics Xiaogan University Xiaogan 432100 China Beijing National Laboratory for Condensed Matter Physics Institute of Physics The Chinese Academy of Sciences Beijing 100080 China

Structural and thermal transitions in the materials with nominal compositions of NaxCoO2 （0.5≤x≤0.75） have been investigated from room temperature to 800 K. In-situ heating transmission electron microscopy observations revealed certain distinctive structural phase transitions commonly existing in this system. A superstructure hexagonal phase, proposed arising from partial Na ordering, appears in this system in a high temperature range. The structural model for the superstructure phase has been given. Measurements of thermogravimetry （TG） and differential thermal analysis （DTA） demonstrated that certain structural phase transitions appear around 430 K. NaxCoO2 is decomposed at a temperature higher than 600 K.

关键词： NaxCoO2 phase transition superstructure

Splitting Process of Na-Birnessite Nanosheet via Transmission Electron Microscopy

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Chinese Physics Letters 2013年第8期30卷 198-201页

作者： li lin MA Chao YANG Huai-Xin li jian-qi Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190

The intermediate phase of hydrothermal synthesis of the Na0.44MnO2(NMO)nanowires is systematically investigated by means of transmission electron microscopy(TEM).The coexistence of Na-birnessite and NMO is commonly observed in the *** NMO nanobelts in general have the width of~15 nm embedded in the(001)oriented Na-birnessite *** is also found that the nanosheets of this intermediate phase often split along the NMO and Na-birnessite *** structural study also shows that the NMO nanobelts prefer to grow along the[001]direction and gives rise to the[001]elongated NMO *** on our TEM observations,the visible lattice mismatch and the resultant strain at the NMO/Na-birnessite interface play a critical role for formation of notable splitting structures in this kind of *** mechanism for the formation of the[001]NMO nanobelt is briefly discussed.

关键词： Electron visible sheets

Recent progress in subatomic particle detection technology

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Frontiers of physics 2013年第5期8卷 548-554页

作者： Zhi-Huan li jian-ling Lou qi-Te li Yu-Cheng Ge Zhe-Wei Yin Yan-lin Ye School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking University Beijing 100871 China

Particle detection technologies have been largely advanced in ,boratory over the past decade. A neutron sphere was built to detect the decay neutron emitted from the implanted unstable nu eleus, whereas a multi-neutron correlation spectrometer was implemented to detect the forward moving neutrons resulting from breakup reactions. Charged particle telescopes are now equipped with double sided Silicon strip detectors which have excellent energy and position resolutions. Large size gas chambers, such as resistive plate chambers, have been developed in order to achieve high Derformances related to timing or position measurements. The advances of these technologies con tribute substantially to such large science project, as LHC-CMS, and to the experiments with the radioactive nucleus beams.

关键词： subatomic particles detection nuclear physics

Energy Optimized Approach Based on Clustering Routing Protocol for Wireless Sensor Networks

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Energy Optimized Approach Based on Clustering Routing Protoc...

Unusually Broadened Spectral Profiles Observed in Solar Prominences

第25届中国控制与决策会议

作者： li jian-qi CAO Bin-fang WANG li Wang Wen-Hu Department of Electronic Engineering Hunan University of Arts and Sciences Department of Physics and Electronics Hunan University of Arts and Sciences

ISBN: (纸本)9781467355339

To realize maximization of the effective coverage area and lifetime for wireless sensor networks monitoring areas, the design of network routing protocol needs to take consideration of both the individual node and the whole network energy consumption. Aiming at the characteristics that node distribution is influenced by natural condition and data can fuse in real environment, as well as signaling overhead in unique uneven EEUC （Energy-Efficient Unequal Clustering protocol）, an improved clustering routing algorithm has been presented, which priority to energy efficiency. First, generate cluster head by random competition in the nodes which have advantage in energy;next determine the internal structure of clusters by calculating dynamically tightness coefficient of each cluster, after that, optimize transmission path between cluster heads through improved multi-objective particle swarm algorithm. Theoretical analysis and simulation results show that new proposed routing protocol can better balance energy consumption improve energy efficiency of the networks and prolong the network lifetime.

关键词： Wireless Sensor Networks routing protocol multi-objective particle swarm optimization energy efficiency

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Chinese Journal of Astronomy and Astrophysics 2004年第4期4卷 377-389页

作者： Huili jian-qiYou EijiroHiei PurpleMountainObservatory ChineseAcademyofSciencesNanjing210008 NationalAstronomicalObservatoryofJapan MitakaTokyo181-8588Japan

After surveying the spectra of 39 prominences observed by the Multi-channel Infrared Solar Spectrograph at Purple Mountain Observatory and the 25 cm coronagraph at the Norikura Solar Observatory, we found that about 28% of them show small spatial scale (6''–8'') and short time scale (tens of seconds to a few minutes), unusual large broadening and large shift velocities in spectral lines including Hα, Hβ, H, Ca II H, Ca II K, Ca II 8542?, He I D3 and He I 10830?. We present in detail two typical events observed respectively on 2002 May 27 and 1981 August 2. The full-width at half maximum of the widest profile of the 2001 prominence is 1.8? for Hα and 2.9 ? for He I 10830?, while that of the 1981 prominence is 5.3 ? for Hβ, 3.6 ? for Ca II K, 4.0 ? for Ca II H and 2.8 ? for He I D3. Such broadenings generally occur at a level of several-thousand kilometres above the chromosphere. Further, most of these prominences manifest a rotation of (0.4–1.35)×10-2 rads s?1 pointing to the Sun and large line-of-sight velocities of 20–200 km s?1. Some of these events correspond in time to an enhancement or a small peak in the GOES X-ray flux, indicating the existence of high energy process at work. These prominences generally display discernible changes in the Hα morphology around the time of large broadening, but do not show Hα brightening or overall eruption except for a few small surge-like events, hence, they are hardly observed in daily Hα patrols. According to the characteristics of their Hα structures and spectral properties, we infer these events are small-scale eruptions similar to nano-flares, which may contribute to the mass and energy transported into the corona. Large turbulent velocities of 25–120 km s?1 are responsible for the observed broadenings.

关键词： sun: prominences line: profiles turbulence

Structural Properties of MgB2 Superconductors with a Critical Current Density Greater than 10^(5)A/cm^(2)

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Chinese Physics Letters 2001年第5期18卷 680-683页

作者： li jian-qi li Long ZHOU Yu-qing REN Zhi-An CHE Guang-Can ZHAO Zhong-Xian National Laboratory for Superconductivity Institute of PhysicsChinese Academy of SciencesBeijing 100080 Department of Physics Ningxia UniversityYinchuan 750021

Structural features of MgB2 superconductors prepared under different conditions have been analysed by means of transmission electron *** MgB_(2) crystal is identified to have a hexagonal structure with the space group of P6/*** materials synthesized under a high pressure of 6 Gpa are made of regularly stacked grains as large as a few microns in *** faults and microstructure properties of grain boundaries either with or without impurities,appearing in a sample with the critical current density greater than 10^(5)A/cm^(2),have been systematically investigated.

关键词： MgB2 (5) Superconductor

氮、磷营养对黄土高原旱地玉米产量、品质的影响机理研究

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植物营养与肥料学报 2008年第6期14卷 1042-1047页

作者：李建奇山东省菏泽学院资源与环境系山东菏泽274030 甘肃农业大学农学院甘肃兰州730070

田间裂区试验研究了不同氮、磷施用水平对旱地玉米子粒产量和品质的影响。结果表明,增施氮、磷肥,能增加子粒粗蛋白、粗脂肪、赖氨酸含量和子粒容重,降低粗淀粉的含量,提高玉米产量和水分利用效率,且氮肥效果优于磷肥。施用氮、磷肥能... 详细信息

田间裂区试验研究了不同氮、磷施用水平对旱地玉米子粒产量和品质的影响。结果表明,增施氮、磷肥,能增加子粒粗蛋白、粗脂肪、赖氨酸含量和子粒容重,降低粗淀粉的含量,提高玉米产量和水分利用效率,且氮肥效果优于磷肥。施用氮、磷肥能够增加土壤碱解氮、速效磷的浓度,有利于玉米根系对氮、磷营养的吸收:在促进根系生长的同时,提高玉米的生物产量,增加植株茎秆、叶片对氮素、磷素的吸收、转化以及向穗轴、子粒的输送,显著提高子粒的灌浆强度,促进灌浆中后期子粒氮、磷的积累.增大粒重,改善子粒品质。

关键词：氮磷营养玉米产量品质机理

Brain endothelial cyclic GMP-AMP synthase(cGAS)-stimulator of interferon genes(STING)signaling pathway in aging and neurodegeneration

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Neural Regeneration Research 2025年第7期20卷 2005-2007页

作者： Bryan Sun Lulin li jian Luo Palo Alto Veterans Institute for Research VA Palo Alto Health Care SystemPalo AltoCAUSA Polytrauma System of Care VA Palo Alto Health Care SystemPalo AltoCAUSA

The cyclic GMP-AMP synthase(cGAS)-stimulator of interferon genes(STING)signaling pathway has emerged as a key mediator of *** current studies primarily attribute its effects to neurons and glial cells,emerging research suggests that cGAS-STING signaling may play a critical role in cerebral vasculature,particularly in brain endothelial ***,studying the role 7of inflammation caused by the cGAS-STING pathway in brain endothelial cells could provide a more comprehensive understanding of neuroinflammatory disease and new avenues for therapeutic ***,we review the multifaceted role of global cGAS-STING signaling in various neurological and neuroinflammatory diseases and the potential contribution of cGAS-STING in brain endothelial cells.

关键词： stimulator interferon inflammation

Prussian Blue Analogue‑Templated Nanocomposites for Alkali‑Ion Batteries:Progress and Perspective

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Nano-Micro Letters 2025年第1期17卷 216-261页

作者： jian‑En Zhou Yilin li Xiaoming lin Jiaye Ye Key Laboratory of Theoretical Chemistry of Environment Ministry of EducationSchool of ChemistrySouth China Normal UniversityGuangzhou 510006People’s Republic of China School of Chemistry and Physics Faculty of ScienceQueensland University of Technology2 George StreetBrisbaneQLD 4000Australia Centre for Materials Science Queensland University of Technology2 George StreetBrisbaneQLD 4000Australia

lithium-ion batteries(liBs)have dominated the portable electronic and electrochemical energy markets since their commercialisation,whose high cost and lithium scarcity have prompted the development of other alkali-ion batteries(AIBs)including sodium-ion batteries(SIBs)and potassium-ion batteries(PIBs).Owing to larger ion sizes of Na^(+)and K^(+)compared with li^(+),nanocomposites with excellent crystallinity orientation and well-developed porosity show unprecedented potential for advanced lithium/sodium/potassium *** enticing open rigid framework structures,Prussian blue analogues(PBAs)remain promising self-sacrificial templates for the preparation of various nanocomposites,whose appeal originates from the well-retained porous structures and exceptional electrochemical activities after thermal *** review focuses on the recent progress of PBA-derived nanocomposites from their fabrication,lithium/sodium/potassium storage mechanism,and applications in AIBs(liBs,SIBs,and PIBs).To distinguish various PBA derivatives,the working mechanism and applications of PBA-templated metal oxides,metal chalcogenides,metal phosphides,and other nanocomposites are systematically evaluated,facilitating the establishment of a structure–activity correlation for these *** on the fruitful achievements of PBA-derived nanocomposites,perspectives for their future development are envisioned,aiming to narrow down the gap between laboratory study and industrial reality.

关键词： Prussian blue analogues Self-sacrificial template lithium-ion batteries Sodium-ion batteries Potassium-ion batteries