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Electrochemical performance of LiNi_(0.5)Mn_(0.5)O_2 with different synthesis methods

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Rare Metals 2015年第8期34卷 580-585页

作者： hong Li Qiang Xu xi-xi Shi Da-Wei Song Lian-Qi Zhang Department of Applied Chemistry School of Chemical and Engineering Tianjin University School of Materials Science and Engineering Tianjin University of Technology

Li Ni0.5Mn0.5O2 as a cathode material for Li-ion battery was prepared by the metal acetate decomposition method, sol–gel method, and carbonate co-precipitation method, respectively. The influences of synthesis methods on the physical and electrochemical behaviors of Li Ni0.5Mn0.5O2 were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM) and electrochemical tests. XRD patterns show that both the sol–gel and carbonate co-precipitation methods can form single phase of layered structure, while a trace of Ni O impurity is observed via the metal acetate decomposition method. SEM results show the as-prepared carbonate particle has a spherical morphology with an average diameter of 10 lm, consisted of primary nano-sized particles with particle diameter of200 nm. The sample prepared by the carbonate co-precipitation method exhibits the highest discharge specific capacity and the best cycling stability, which results from the steady homogeneity of precursor constant by the fixation of CO2-3group. It can deliver an initial discharge specific capacity of 186.3 m Ahág-1, and retain 170 m Ahág-1after100 cycles at a current rate of 20 m Aág-1in the voltage range of 2.5–4.7 V at 25 °C. Moreover, even at the high temperature of 55 °C, it still delivers a reversible specific capacity of 222.6 m Ahág-1with little capacity loss after 30 cycles.

关键词： Sol–gel Carbonate co-precipitation LiNi0.5Mn0.5O2

Development of Hybrid Rice Variety FY7206 with Blast Resistance Gene Pid3 and Cold Tolerance Gene Ctb1

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Rice science 2016年第5期23卷 266-273页

作者： xiE hong-guang JIANG Jia-huang ZHENG Yan-mei ZHU Yong-sheng WU Fang-xi LUO xi CAI Qiu-hua ZHANG Jian-fu xiE Hua-an Rice Research Institute Fujian Academy of Agricultural Sciences

Hybrid rice Fanyou 7206（FY7206）, derived from the cross between a sterile line Fanyuan A and a restorer line Fuhui 7206, was bred by the Rice Research Institute, Fujian Academy of Agricultural Sciences, China. FY7206 was characterized by moderate blast resistance, cold tolerance, as well as wide adaptability, and high yields. The blast resistance results indicated that the frequencies of blast races in race B, race C and the total resistance frequency for FY7206 were 95.5%, 100.0% and 97.2%, respectively. The disease resistance results showed that the leaf blast grade for FY7206 was level 1 and panicle blast was level 5. The indoor spray results indicated that FY7206 was resistant to 11 isolates of Magnorpathe oryzae. The blast resistance of FY7206 might be derived from the high expression of blast resistance gene Pid3. The results for simulated cold resistance in an artificial climate chamber indicated that the cold tolerance for FY7206 was moderate at the booting and flowering stages. The cold tolerance results also indicated that FY7206 could be tolerant to temperatures as low as 10 °C at the seedling stage. The q RT-PCR results showed that the expression of cold tolerance gene Ctb1 in FY7206 was relatively high. These results suggested that FY7206 is a hybrid indica rice variety with good comprehensive characteristics, including blast resistance and cold tolerance.

关键词： hybrid rice blast resistance gene Pid3 cold tolerance gene Ctb1 yield breeding

"Solid-Liquid" Vitrimers Based on Dynamic Boronic Ester Networks

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Chinese Journal of Polymer Science 2021年第10期39卷 1292-1298,I0006页

作者： sheng Wang Lu-Lu Xue xiao-Zhuang Zhou Jia-xi Cui INM-Leibniz Institute for New Materials Campus D22 Saarbrucken 66123Germany Beijing National Laboratory for Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054China

The"solid-liquid"behavior of vitrimers have not been systematically ***,a series of"solid-liquid"vitrimers bearing varying contents of dynamic boronic ester bonds were synthesized via thiol-ene click *** vitrimers allow for flexibile modulation of their network structures and thus show a range of intriguing properties including high stretchability,flexible transition from elasticity to plasticity,strong strain rate dependence,and solid-liquid *** dynamic association rate of boronic ester bonds within these vitrimers could be apparently accelerated via increasing the content of boronic ester,which could be used to shape-program the flat vitrimer films into various complex 3D structures just with external *** with such versatile dynamic behavior may open up a range of new applications.

关键词： Solid-liquid Dynamic covalent bond Boronic ester bond Strain-rate dependent High stretchability

Quantum Phase Transitions in Spin Star Configuration

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Communications in Theoretical Physics 2008年第5期49卷 1353-1356页

作者： DENG hong-Liang FANG xi-Ming Key Laboratory of Quantum Structure and Quantum Control of Ministry of Education and Department of Physics Hunan Normal University Changsha 410081 China

We consider a generalized spin star configuration that can be solved exactly, with the central spin-1/2 system embedded in an outer ring of N spin-1/2 particles （denoted as spin bath）. In this model, we consider a modified version of the spin star model, by taking into account, besides the interaction of the central spin with the bath, the interactions between the spins of the bath as well. The general expressions of the eigenstates as well as the eigenvalues of the model are derived with the use of the symmetries of system. We then investigate the properties of the ground quantum phase transitions in some limiting cases in the model and show that the occurrence of quantum phase transitions and the desired ground states can be obtained by varying the external control parameters.

关键词： quantum phase transitions ground state

Settlement Prediction for Buildings Surrounding Foundation Pits Based on a Stationary Auto-regression Model

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Journal of China University of Mining and Technology 2007年第1期17卷 78-81页

作者： TIAN Lin-ya HUA xi-sheng College of Civil Engineering Hohai University Nanjing Jiangsu 210098 China

To ensure the safety of buildings surrounding foundation pits, a study was made on a settlement monitoring and trend prediction method. A statistical testing method for analyzing the stability of a settlement monitoring datum has been discussed. According to a comprehensive survey, data of 16 stages at operating control point, were verified by a standard t test to determine the stability of the operating control point. A stationary auto-regression model, AR(p), used for the observation point settlement prediction has been investigated. Given the 16 stages of the settlement data at an observation point, the applicability of this model was analyzed. Settlement of last four stages was predicted using the stationary auto-regression model AR (1); the maximum difference between predicted and measured values was 0.6 mm, indicating good prediction results of the model. Hence, this model can be applied to settlement predictions for buildings surrounding foundation pits.

关键词： foundation pit building settlement monitoring datum stability stationary auto-regression model settlement prediction

Is traumatic meniscal lesion associated with acute fracture morphology changes of tibia plateau? A series of arthroscopic analysis of 67 patients

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World Journal of Clinical Cases 2021年第1期9卷 81-90页

作者： Yan-Dong Chen Shu-xiang Chen hong-Guang Liu xiang-sheng Zhao Wen-Huan Ou Huan-xi Li hong-xing Huang 3^rd Institute of Clinical Medicine Guangzhou University of Chinese MedicineGuangzhou 510000Guangdong ProvinceChina Department of Joint Trauma Jiangmen Wuyi Hospital of Traditional Chinese MedicineAffiliated Jiangmen Traditional Chinese Medicine Hospital of Jinan UniversityJiangmen 529031Guangdong ProvinceChina Department of Radiology Jiangmen Wuyi Hospital of Traditional Chinese MedicineJiangmen 529031Guangdong ProvinceChina Science and Education Section The Third Affiliated Hospital of Guangzhou University of Chinese MedicineGuangzhou 510378Guangdong ProvinceChina

BACKGROUND Computed tomography(CT)has become a routine preoperative examination for tibial plateau fractures(TPFs).Assessing the location of the fragment and intercondylar eminence fracture can provide clinicians with valuable information;however,the evaluation of traumatic meniscal lesion(TML)and arthroscopic management are *** To predict TML by three-dimensional skeletal anatomy changes in unilateral TPF and bilateral TPF on preoperative thin layer *** Acute fracture of tibial plateau patients undergoing arthroscopic surgery between December 2017 and December 2019 were included in this retrospective *** type,zone,and location of TMLs were diagnosed based on the operation records and/or arthroscopic *** of three-dimensional fracture morphology included the following:Frontal fragment width of plateau,sagittal fragment subsiding distance(FSD),sagittal fracture line distance,sagittal posterior tibial slope,and transversal area ratio of fragment area)on preoperative CT three-dimensional *** correlation of TML with skeletal values was calculated according to unicondylar TPFs and bicondylar *** A total of 67 patients were enrolled in this study,among which 30 patients had TMLs,lateral/medial(23/7).FSD was a particularly positive factor to predict TML,with odds ratio of 2.31(1.26-5.63).On sagittal view of CT,FSD degree of 8 mm and posterior tibial slope exceeding 11.74°implied enhanced risk of TML in bicondylar *** coronal view,once fragment width of plateau surpassed 3 cm,incidence of TML reached 100%.On transverse view,area ratio of fragment as enhanced risk of 5.5%and FSD>4.3 mm for predicting TML were observed in unicondylar *** TML can be predicted by different parameters on preoperative CT views according to unicondylar fractures and bicondylar TPFs.

关键词： Traumatic meniscal lesion Knee Three-dimensional computerized tomography Posterior tibial slope Unicondylar fracture Bicondylar fracture

Estimating the Delay-time for the Stability of Markovian Jump Bilinear Systems with Saturating Actuators

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自动化学报 2010年第5期36卷 762-766页

作者： KANG Yu SHANG Wei-Ke xi hong-sheng Department of Automation University of Science and Technology of China Hefei 230026 P.R. China

This paper is concerned with the stochastic stabilizability problem of time-delay Markovian jump bilinear systems with saturating *** conditions for local exponential stochastic stability of the delay-free systems with memoryless state feedback control are given, and an upperbound of time delay is provided such that the delayed system retains its stochastic stabilizability if the corresponding delay-free system is stochastic stabilizable. A numerical example is provided to demonstrate the effectiveness of the proposed approach

关键词：马尔可夫链线性系统可靠性稳定性

Cross-layer scheduling with fairness for multi-user OFDM system:a restless bandit approach

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The Journal of China Universities of Posts and Telecommunications 2011年第4期18卷 25-30页

作者： GE Wen-dong JI hong LI xi Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

In OFDM-based System such as long term evolution （LTE）, the scheduling scheme plays an essential role in not only improving the capacity of system, but also guarantee the fairness among the user equipments （UEs）. However, most existing work about scheduling only considers the current throughput in physical layer. Thus in this paper, a cross-layer scheduling with fairness based on restless bandit （CSFRB） scheme with the ＇indexability＇ property is proposed for the multi-user orthogonal frequency-division multiplexing （OFDM） system to minimize the distortion in the application layer, to maximize the throughput and to minimize the energy consumption in the physical layer. The scheduling problem is firstly established as a restless bandit problem, which is solved by the primal-dual index heuristic algorithm based on the first order relaxation with low complexity, to yield the CSFRB scheme. AdditionaUy, this scheme is divided into offiine computation and online selection, where main work will be finished in former one so as to decrease the complexity further. Finally, extensive simulation results illustrate the significant performance improvement of the proposed CSFRB scheme compared to the existing one in different scenarios.

关键词： multi-user OFDM scheduling cross-layer design restless bandits

TURBULENT OPEN CHANNEL FLOW SUBJECTED TO THE CONTROL OF A SPANWISE TRAVELING WAVE

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Journal of Hydrodynamics 2009年第1期21卷 65-70页

作者： LIU Nan-sheng WANG Lei LU xi-yun Department of Modem Mechanics University of Science and Technology of China Hefei 230026 China

Turbulent open channel flows subjected to the control of a spanwise traveling wave have been investigated by means of Direct Numerical Simulation （DNS）. The objective of this study is to reveal the response of the near-wall and surface-influenced turbulence to the spanwise traveling wave control. Three typical frequencies of the spanwise traveling wave, i.e., high-, middle- and low-frequency, corresponding to the exciting periods at 25, 50 and 100, are considered to study the turbulence dynamics in the wall and surface regions. To elucidate the behaviors of turbulence statistics, some typical quantities, including the mean velocity, velocity fluctuations and the structures of turbulence fluctuations, are exhibited and analyzed.

关键词： turbulent open channel flow traveling wave Direct Numerical Simulation (DNS) turbulence statistics turbulence structures