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Chinese Chemical Letters 2011年第9期22卷 1099-1102页

作者： wan Min liu Guo rong Hu Zhong Dong Peng Ke Du Yan Bing Cao Qiang liu School of Metallurgical Science and Engineering Central South University Changsha 410083 China School of Chemistry and Chemical Engineering Hunan Institute of Engineering Xiangtan 411104 China

Spherical LiNi0.8Co0.15Al0.05O2 OOH precursor prepared by a co-oxidation-controlled crystallization method, was used to synthesize LiNi0.5Co0.15Al0.05O2. The obtained LiNi0.8Co0.15Al0.05O2 materials showed excellent electrochemical performance, with an initial discharge capacity of 193.5 mAh/g and capacity retention of 95.1% after 50 cycles when cycled at 0.2 C rate between 2.8 and 4.3 V.

关键词： Li-ion battery Cathode material LiNi0.8Co0.15Al0.05O2 Co-oxidation-controlled crystallization

A Blockwall-Type Layered Bis(dithiolato)nickelate Radical Salt Exhibiting High-and Two-Dimensional Antiferromagnetic Coupling Feature

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Chinese Journal of Chemistry 2022年第7期40卷 794-800页

作者： wan-wan Yao Yin Qian Xuan-rong Chen Xiao-Ming Ren State Key Laboratory of Materials-Oriented Chemical Engineering and College of Chemistry&Molecular Engineering Nanjing Tech UniversityNanjingJiangsu 211816China School of Chemistry&Environmental Engineering and Instrumental Analysis Center Yancheng Teachers University YanchengJiangsu 224007China

The family of[M(dmit)_(2)]-salts(dmit2-=2-thioxo-1,3-dithiole-4,5-dithiolate;M=Ni,Pd and Pt)generally show novel magnetic,elec-tric,magnetoelectric and photoelectric ***,a blockwall-type layered[Me3S][Ni(dmit)_(2)]radical salt(1;Me3S+=trime-thylsulfonium)was prepared and characterized by microanalysis,IR spectroscopy,thermal analysis,powder and single crystal X-ray diffraction *** 1 crystalizes in triclinic space group P-1,with two pairs of[Ni(dmit)_(2)]-and Me3S+ions in an asymmetric *** anions form blockwall-type monolayer,being parallel to crystallographic(011)plane,and the cations are accommodated in the spaces of anion *** 1 features a two-dimensional S=1/2 antiferromagnetic(AFM)spin system withθ=-97.8(1)K and a semiconductor withσ≈10-4 S·cm^(-1) and activation energy Ea=0.24(1)eV in 308-368 K.1 shows two-step dielectric relaxa-tions ranged from 173-373 K and 1-107 Hz for the dipole motions of two different polar *** importantly,the dielectric constant of 1 reaches to~17,with high-κ*** study suggests the possibility of achieving high-K materials by introducing po-lar and low rotation barrier components into van der Waals crystal and high-K[Ni(d m it)_(2)]--based electrode materials for applications in supercapacitors.

关键词： Metal-dithiolene complex Radical ionshigh-κ Semiconductors Magnetic properties

Generating Even-Photon State via Resonant Interaction Between Ladder-Type Three-Level Atoms with a Single-Mode Field

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Communications in Theoretical Physics 2008年第1期49卷 221-224页

作者： ZHONG Zhi-rong SU wan-Jun Department of Electronic Science and Applied Physics Puzhou University Puzhou 350002 China

A scheme is presented to generate even-photon state based on resonant interaction between ladder-type three-level atoms with a single-mode field. In the scheme, a sequence of suitably prepared ladder-type three-level atoms are orderly sent through a single-mode cavity initiaJly in vacuum state. The detection of a J1 the atoms in the ground states collapses the cavity to the desired state. The scheme is based on the resonant interaction of atoms with the cavity, and thus the required interaction time can be greatly shortened. This is important in view of decoherence.

关键词： even photon state resonant interaction ladder-type atom

Low-frequency electrical stimulation improves neurite outgrowth of dorsal root ganglion neurons in vitro via upregulating Ca^(2+)-mediated brain-derived neurotrophic factor expression

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Neural Regeneration Research 2010年第16期5卷 1256-1260页

作者： Lidan wan rong Xia Wenlong Ding Department of Anatomy Shanghai Jiao Tong University School of Medicine Shanghai 200025 China Department of Anatomy Medical College of Nanchang University Nanchang 330006 Jiangxi Province China

Short-term, low-frequency electrical stimulation of neural tissues significantly enhances axonal regeneration of peripheral nerves following injury. However, little is known about the mechanisms of electrical stimulation to induce neurite outgrowth. In the present study, short-term, low-frequency electrical stimulation, using identical stimulation parameters of in vivo experiments, was administered to in vitro dorsal root ganglion （DRG） neurons. Enhanced neurite outgrowth, as well as synthesis and release of brain-derived neurotrophic factor （BDNF）, were examined in electrical stimulation-treated DRG neuronal cultures. Because the effects of electrical stimulation on neuronal intracellular signaling molecules are less reported, classic calcium intracellular signals are directly or indirectly involved in electrical stimulation effects on neurons. Cultured DRG neurons were pretreated with the calcium channel blocker nifedipine, followed by electrical stimulation. Results suggested that electrical stimulation not only promoted in vitro neurite outgrowth, but also enhanced BDNF expression. However, nifedipine reduced electrical stimulation-enhanced neurite outgrowth and BDNF biosynthesis. These results suggest that the promoting effects of electrical stimulation on DRG neurite outgrowth could be associated with altered calcium influx, which is involved induction of neuronal BDNF expression and secretion.

关键词： electrical stimulation dorsal root ganglion neurons neurite outgrowth brain-derived neurotrophic factor Ca2+ neural regeneration

New understanding achieved from 2 years of Chinese ionospheric investigations

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Science Bulletin 2016年第7期61卷 524-542页

作者： Libo liu Weixing wan Key Laboratory of Earth and Planetary Physics Institute of Geology and Geophysics Chinese Academy of Sciences Beijing National Observatory of Space Environment Institute of Geology and Geophysics Chinese Academy of Sciences Geoscience School University of the Chinese Academy of Sciences

In the mainland of China, the number of ionospheric research groups is more than 10. Around 110 articles related to ionospheric physics have been published during 2014–2015. In this annual national report of the Committee on Space Research(COSPAR), we will outline some recent progresses in ionospheric studies conducted by the Chinese mainland scientists in the past 2 years. These investigations cover(1) the ionosphere responses to geomagnetic activities;(2) ionospheric climatology and structures;(3) couplings between the ionosphere, plasmasphere and lower atmosphere, and possible seismic signatures in the ionosphere;(4) ionospheric irregularities and scintillation;(5) ionospheric models, data assimilation and simulations;(6) ionospheric dynamics and electrodynamics;(7) progresses in the observation methodology and technique; and(8) planetary ionospheres. Such investigations will strengthen our ability to monitor the ionosphere,provide a better understanding of the ionospheric states and the underlying fundamental processes, and improve the ionospheric modeling, forecasting, and related applications.

关键词： Ionosphere Ionospheric climatology Ionospheric dynamics Ionospheric coupling Planetary ionospheres Ionospheric disturbance

A comprehensive fractal char combustion model

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Chinese Journal of Chemical Engineering 2016年第12期24卷 1750-1760页

作者： Yuting liu rong He Department of Thermal Engineering Tsinghua University Institute of Materials China Academy of Engineering Physics

The char combustion mechanisms were analyzed and a comprehensive fractal char combustion model was developed to give a better understanding and better predictions of the char combustion characteristics. Most of the complex factors affecting the char combustion were included, such as the coupling effects between the pore diffusion and the chemical reactions, the evolution of the char pore structures and the variation of the apparent reaction order during combustion, the CO/CO_2 ratio in the combustion products and the correction for oxy-char combustion. Eleven different chars were then combusted in two drop tube furnaces with the conversions of the partly burned char samples measured by thermogravimetric analysis. The combustion processes of these chars were simulated with the predicted char conversions matching very well with the measured data which shows that this char combustion model has good accuracy. The apparent reaction order of the char combustion decreases, stabilizes and then increases during the combustion process. The combustion rates in the oxy-mode are generally slower than in the air-mode and the effect of the char-CO_2 gasification reaction becomes obvious only when the temperature is relatively high and the O_2 concentration is relatively low.

关键词： Combustion Model Experimental validation Pore Fractals

Zero-Hopf bifurcation for an infection-age structured epidemic model with a nonlinear incidence rate

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Science China Mathematics 2017年第8期60卷 1371-1398页

作者： liu ZhiHua YUAN rong School of Mathematical Sciences Beijing Normal University

An infection-age structured epidemic model with a nonlinear incidence rate is *** formulate the model as an abstract non-densely defined Cauchy problem and derive the condition which guarantees the existence and uniqueness for positive age-dependent equilibrium of the *** analyzing the associated characteristic transcendental equation and applying the normal form theory presented recently for non-densely defined semilinear equations,we show that the SIR(susceptible-infected-recovered)epidemic model undergoes Zero-Hopf bifurcation at the positive equilibrium which is the main result of this paper.

关键词： infection-age structured epidemic non-densely defined stability normal form zero-Hopf bifurcation

Dielectric thin films for GaN-based high-electron-mobility transistors

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Rare Metals 2015年第6期34卷 371-380页

作者： Yan-rong Li Xing-Zhao liu Jun Zhu Ji-Hua Zhang Lin-Xuan Qian wan-Li Zhang State Key Laboratory of Electronic Thin Films and Integrated Devices School of Microelectronics and Solid-State Electronics University of Electronic Science and Technology of China

The effects of dielectric thin films on the performance of GaN-based high-electron-mobility transistors （HEMTs） were reviewed in this work. Firstly, the nonpolar dielectric thin films which act as both the surface passivation layers and the gate insulators of the high-frequency GaN-based high-electron-mobility transistors were presented. Furthermore, the influences of dielectric thin films on the electrical properties of two-dimensional electron gas （2DEG） in the A1GaN/GaN hetero-structures were ana- lyzed. It was found that the additional in-plane biaxial tensile stress was another important factor besides the change in surface potential profile for the device perfor- mance improvement of the A1GaN/GaN HEMTs with dielectric thin films as both passivation layers and gate dielectrics. Then, two kinds of polar gate dielectric thin films, the ferroelectric LiNbO3 and the fluorinated A1203, were compared for the enhancement-mode GaN-based HEMTs, and an innovative process was proposed. At last, high-permittivity dielectric thin films were adopted as passivation layers to modulate the electric field and accordingly increase the breakdown voltage of GaN-based HEMTs. Moreover, the polyimide embedded with Cr particles effectively increased the breakdown voltage of GaNbased HEMTs. Finally, the effects of high-permittivity dielectric thin films on the potential distribution in the drift region were simulated, which showed an expanded electric field peak at the drain-side edge of gate electrode.

关键词： GaN-based HEMTs Surface passivation Gate dielectrics Enhancement-mode HEMTs High-permittivity field plate

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双因子显式二阶积分法

Effect of precipitates on high-temperature strength and irradiation behavior of vanadium-based alloys

工程力学 2025年第1期42卷 20-31页

作者：刘慧鹏刘付钧周福霖傅向荣广州大学工程抗震中心广州510006 广州容联建筑科技有限公司广州510180 中国农业大学土木工程系北京100083

研究了一类超收敛的显式二阶积分方法。该方法从哈密顿体系动力相场出发，利用二阶泰勒展开式，构造了动力时程分析迭代算法的基本格式。采用高斯积分处理在迭代步内荷载项的积分，并引入超收敛因子\begin{document}$ \alpha $\end{docu... 详细信息

研究了一类超收敛的显式二阶积分方法。该方法从哈密顿体系动力相场出发，利用二阶泰勒展开式，构造了动力时程分析迭代算法的基本格式。采用高斯积分处理在迭代步内荷载项的积分，并引入超收敛因子\begin{document}$ \alpha $\end{document}和\begin{document}$ \beta $\end{document}来提高算法的收敛步长和计算稳定性。该方法避免了整体刚度矩阵的求逆和相乘，因此不需要进行整体刚度矩阵的组集，是一种快速的新型动力显式积分法。引入超收敛因子后，该算法可大幅提高收敛步长，可在理论时间步长下稳定收敛。数值算例表明：双因子超收敛显式二阶积分法比传统精细积分法具有更高算法稳定性和精度;在合适分析步长下可与常用积分算法保持一致的精度和稳定性，且随着分析步长的增大具有更好的精度稳定性。

关键词：精细积分显式积分超收敛动力时程分析哈密顿体系

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Journal of Iron and Steel Research International 2018年第12期25卷 1270-1277页

作者： Shao-ning Jiang Li-qun Xu Fa-rong wan School of Mechanical and Automotive Engineering Qilu University of Technology (Shandong Academy of Science) Jinan 250353ShandongChina School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

The formation of precipitates and their effect on mechanical properties and irradiation damage in V-4CraTi alloys have been investigated using transmission electron microscope,high-temperature tensile tests and high-voltage electron microscope (HVEM).V-4Cr-4Ti alloys were aged for 20-40 h at 873 K,and extremely fine precipitates were produced during the aging process,which coarsened with aging *** results of high-temperature (773,873 and 973 K)tensile tests showed an increase in strength with increasing aging time (i.e:,increasing size of precipitates)while a decrease in the uniform *** was evidence that presence of precipitates strengthened V-4Cr-4Ti *** situ HVEM observations showed that the precipitates restricted the growth rate of dislocation loops induced during electron irradiation at 773 *** interactions between precipitates and irradiation-induced dislocation loops were *** presence of particles alleviated the increase in irradiation hardening up to an irradiation dose of 3.42 dpa (displacement per atom).The precipitates shrank in size during electron irradiation,which was due to the dissolution of constituent atoms of the precipitates into the alloy matrix.

关键词： Aging Precipitate strengthening Electron irradiation Irradiation defect Dislocation loop