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Science China Chemistry 2010年第3期53卷 542-551页

作者： Fang, Ya hui Liu, Zhi pan Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of Chemistry Fudan University Shanghai 200433 China

Theoretical simulations on complex electrochemical processes have been developed on the basis of the understanding in electrochemistry,which has benefited from quantum mechanics *** article reviews the recent progress on the theory and applications in *** representative reactions,namely water electrolysis and oxygen reduction,are selected to illustrate how the theoretical methods are applied to electrocatalytic *** microscopic nature of these electrochemical reactions under the applied potentials is described and the understanding of the reactions is *** thermodynamics and kinetics of the electrochemical reactions affected by the interplay of the electrochemical potential,the bonding strength and the local surface structure are addressed at the atomic level.

关键词： density functional theory electrode/solution interface water electrolysis oxygen reduction reaction review

Fabrication and application of arrays related to two-dimensional materials

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Rare Metals 2022年第1期41卷 262-286页

作者： hui-Li Jiang Jia pan Wei Zhou hui-Min Li Song Liu Institute of Chemical Biology and Nanomedicine(ICBN) State Key Laboratory of Chemo/Biosensing and ChemometricsCollege of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China

In recent years,two-dimensional(2D)materials have attracted extensive attention from researchers for their unique structures and electrical properties.2D materials have been widely applied in field effect transistors,sensors,and *** is extremely important for practical applications in devices,which requires both minimal crosstalk and high *** fabrication of patterned arrays of 2D materials can realize high-density *** addition,the properties of 2D materials can be also adjusted by the patterned *** this review,we summarize the emerging researches related to 2D materials and ***,the preparation strategies of different arrays have been ***,the applications of arrays have been investigated,such as physical unclonable functions,sensors,energy consumption,photoluminescence enhancement,quantum emitters and ***,the prospects and existing challenges have been proposed.

关键词： 2D materials 2D material arrays Sensors Quantum emitters Photodetectors

Quantum heat engine cycle working with a strongly correlated electron system

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Science China(Physics,Mechanics & Astronomy) 2012年第5期55卷 792-797页

作者： WANG HaiLong pan hui WANG RongMing Department of Physics and State Key Laboratory of Software Development Environment Beijing University of Aeronautics and AstronauticsBeijing 100191China Key Laboratory of Micro-nano Measurement-Manipulation and Physics(Ministry of Education)and Department of Physics Beijing University of Aeronautics and AstronauticsBeijing 100191China

A new model of a quantum heat engine （QHE） cycle is established, in which the working substance consists of an interacting electrons system. One of our purposes is to test the validity of the second law of thermodynamics by this model, which is more general than the spin-1/2 antiferromagnetic Heisenberg model since it would recover the spin model when the on-site Coulomb interaction U is strong enough. On the basis of quantum mechanics and the first law of thermodynamics, we show no violation of the second law of thermodynamics during the cycle. We further study the performance characteristics of the cycle by investigating in detail the optimal relations of efficiency and dimensionless power output. We find that the efficiency of our engine can be expressed as η = t22/t21 in the large-U limit, which is valid even for a four sites QHE.

关键词： quantum heat engine strongly correlated electrons Hubbard model

DEVELOPMENT AND APPLICATIONS OF THE ELASTO-PLASTIC CELLULAR AUTOMATON

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Acta Mechanica Solida Sinica 2012年第2期25卷 126-143页

作者： Pengzhi pan Xiating Feng hui Zhou State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China

The paper presents the advancement and applications of the elasto-plastic cellular automaton （EPCA）, a simulator for rock mechanics and rock engineering. The most significant feature of EPCA lies in its ＇down-top＇ way of dealing with nonlinear behaviors of rocks. The theory, the basic idea and associated developments, including the definition of cellular automaton, the heterogeneous material model, constitutive relations, failure criteria, the post-yield softening scheme, the thermo-hydro-mechanical coupling process, are described. The applications are presented to show the ability of EPCA to model the rock failure process, fluid flow, heat transfer, and the coupled thermo-hydro-mechanical （THM） process etc.

关键词： rock failure process elasto-plastic cellular automaton complete stress-strain curves,fluid flow heat transfer thermo-hydro-mechanical coupling

Secrecy outage analysis on underlay cognitive radio using selection combining

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The Journal of China Universities of Posts and Telecommunications 2016年第3期23卷 51-56页

作者： Tan Youyu pan Gaofeng Zhao hui School of Electronic and Information Engineering Southwest University

Secure data transmission in future high-capacity high-coverage multi-tier hierarchical networks, for which cognitive radio （CR） has emerged as an essential recipe, is of utmost importance. This paper investigates the secrecy outage performance of selection combining （SC） in CR networks （CRNs） over Rayleigh fading channels. In a single-input multiple-output （SIMO） wiretap channel, a secondary user transmits confidential messages to another secondary user, which is equipped with n B （nB ≥1） antennas. Meanwhile, a passive eavesdropper, which is equipped with nE （n E ≥1） antennas, intends to overhear the messages. Both the legal receiver and the eavesdropper adopt SC scheme to process the received multiple signals. The secondary transmitter uses the underlay strategy to guarantee the quality of service of the primary user without spectrum sensing. Compared to the work proposed by Maged Elkashlan et al. in Ref. [ 1 ], we present an alternative method to derive the closed-form expression for the secrecy outage probability （SOP） and develop a simplified SOP when the maximal transmit power at the secondary user is sufficiently high. Our results reveal the impact of the primary network on the secondary network with a multi-antenna wiretap channel and simulations are conducted to validate the accuracy of our proposed analytical models.

关键词： secrecy outage probability cognitive radio selection combining underlay

An acetic acid refluxing-electrochemistry combined strategy to activate supported-platinum electrocatalysts

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Particuology 2017年第1期15卷 111-117页

作者： Yan Feng Jinding pan hui Liu Jun Yang State Key Laboratory of Multiphase Complex Systems Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China University of ChineseAcademy of Sciences No. 19A Yuquan Road Beijing 100049 China Center for Mesoscience Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China

Surfactant removal from the surface of platinum-based nanoparticles prepared using solution-based methods is a prerequisite to realize their high catalytic performance for electrochemical reactions. Herein, we report an effective approach combining acetic acid refluxing with an electrochemical process for the removal of amine- or thiol-based capping agents from the surface of supported-platinum nanoparticles. This strategy involves surfactant protonation by refluxing the supported-platinum particles in acetic acid followed by surfactant removal by subsequent electrochemical treatment at high potential. We demon- strate that this combined activation process is essential to enhance platinum particle performance in catalyzing direct methanol fuel cell reactions, including methanol oxidation and oxygen reduction reac- tions. The studies in this work show promise in electrocatalysis applications of solution-based materials synthesis.

关键词： Platinum Nanoparticle Methanol oxidation reaction Oxygen reduction reaction Electrocatalysis

Effects of Y2O3 on the microstructure and mechanical properties ofspark plasma sintered fine-grained W-Ni-Mn alloy

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Journal of Rare Earths 2017年第11期35卷 1149-1155页

作者： Yanlin pan Lei Ding hui Li daoping Xiang State Key Laboratory of Marine Resource Utilization in South China Sea Hainan University Haikou 570228 China Key Laboratory for Advanced Materials in Tropical Island Resources Ministry of Education Hainan University Haikou 570228 China

Fine-grained W-Ni-Mn-YOalloys were fabricated by mechanical alloying-assisted spark plasma sintering(SPS), and the effects of YOcontent on the microstructure and mechanical properties of the alloys were studied. Fine-grained 90 W-6 Ni-4 Mn-YOalloys with uniform microstructure and excellent properties were prepared by SPS at 1150 ℃. The addition of trace YOinhibited the sintering densification process and refined the W grain size. The average W grain size decreased from 5.5 μm to 2.1 μ*** fracture mode changed from W grain transgranular fracture and W-W interface fracture to W-W and W-Matrix phase interface fracture. The Rockwell hardness and bending strength of alloys initially increased and then decreased with increasing YOcontent. The optimum comprehensive mechanical properties(Rockwell hardness and bending strength) of the alloys were obtained at the same time when the mass fraction of YOwas 0.4%.

关键词： 90W-6Ni-4Mn alloys Y_2O_3 Spark plasma sintering Bending strength Fracture morphology

Changes in sensorimotor regions of the cerebral cortex in congenital amusia:a case-control study

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Neural Regeneration Research 2021年第3期16卷 531-536页

作者： Jun-Jie Sun Xue-Qun pan Ru Yang Zhi-Shuai Jin Yi-hui Li Jun Liu da-Xing Wu Department of Radiology the Second Xiangya Hospital of Central South UniversityChangshaHunan ProvinceChina Department of Radiology the Affiliated Zhuzhou Hospital of Xiangya College of MedicineCentral South UniversityZhuzhouHunan ProvinceChina Lister Hill National Center for Biomedical Communication National Library of MedicineBethesdaMDUSA Medical Psychological Center the Second Xiangya Hospital of Central South UniversityChangshaHunan ProvinceChina

Perceiving pitch is a central function of the human auditory system;congenital amusia is a disorder of pitch *** underlying neural mechanisms of congenital amusia have been actively ***,little attention has been paid to the changes in the motor rain within congenital *** this case-control study,17 participants with congenital amusia and 14 healthy controls underwent functional magnetic resonance imaging while resting with their eyes closed.A voxel-based degree centrality method was used to identify abnormal functional network centrality by comparing degree centrality values between the congenital amusia group and the healthy control *** found decreased degree centrality values in the right primary sensorimotor areas in participants with congenital amusia relative to controls,indicating potentially decreased centrality of the corresponding brain regions in the auditory-sensory motor feedback *** found a significant positive correlation between the degree centrality values and the Montreal Battery of Evaluation of Amusia *** conclusion,our study identified novel,hitherto undiscussed candidate brain regions that may partly contribute to or be modulated by congenital *** evidence supports the view that sensorimotor coupling plays an important role in memory and musical *** study was approved by the Ethics Committee of the Second Xiangya Hospital,Central South University,China(***20180101GZ01)on February 9,2019.

关键词： congenital amusia degree centrality lifelong impairment local functional connectivity music discrimination primary motor area primary sensorimotor area primary sensory area resting-state functional magnetic resonance imaging voxel-based analysis

Theoretical Study of the AIEt3-Promoted Tandem Reductive Rearrangement of Epoxides

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Chinese Journal of Chemical Physics 2008年第6期21卷 547-554页

作者： Li-dong Zhang hui-jun Guo Yang pan Fei Qi National Synchrotron Radiation Laboratory University of Science and Technology of China Hefei 230029 China

The AIEt3-promoted tandem reductive rearrangement reactions of epoxides was studied at B3LYP/6- 31C（d,p） level. For the model compound α-hydroxy epoxides, two possible reaction pathways Ⅰ and Ⅱ were calculated. The main difference is the order of ethylene release and six- to five-member ring rearrangement. The ring contraction rearrangement in pathway Ⅰ is the first step and this step is the rate controlling step with a free energy barrier of 116.62 kJ/mol. For pathway Ⅱ, the ethylene release occurs first, and is followed by a six-member ring opening reaction which is the rate controlling step, and the barrier is 251.38 kJ/mol. The reason for such high barrier is that the ethylene release results in the following reaction being more difficult. The results show that pathway Ⅰ （C-C rearrangement and then ethylene release） is more favorable, which is consistent with experimental results.

关键词： AIEt3 Rearrangement Density functional theory Diol Epoxide

Changes in corneal nerve morphology and function in patients with dry eyes having type 2 diabetes

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World Journal of Clinical Cases 2022年第10期10卷 3014-3026页

作者： Wei Fang Zhong-Xi Lin hui-Qing Yang Lei Zhao da-Chuan Liu Zhi-Qiang pan Department of Ophthalmology Xuanwu HospitalCapital Medical UniversityBeijing 100053China Department of Ophthalmology Beijing Tongren Eye CenterBeijing Tongren HospitalCapital Medical UniversityBeijing 100005BeijingChina Department of Neurology Xuanwu HospitalCapital Medical UniversityBeijing 100053China Department of Endocrinology Xuanwu HospitalCapital Medical UniversityBeijing 100053China

BACKGROUND Dry eye syndrome(DES)is a common disease with various clinical *** had a significant association with *** reflex(BR)is also known as trigeminal nerve facial *** stimulation of corneal nerves is one of the origins of BR *** parasympathetic fibers sent out through the facial nerve are the outlet of tear *** can be used to assess the function of the corneal nerve closed-loop;however,whether the BR changes in these patients is *** To understand the morphology and function of the corneal nerve in patients with dry eyes having diabetes or *** This study enrolled 131 patients who visited the inpatient and outpatient services of ophthalmology and endocrinology departments between January 2019 to August 2020 with subjective symptoms of dry eyes and non-dry eye reasons,as well as volunteers such as *** patients were divided into four groups:DEwDM,with dry eyes having type 2 diabetes mellitus(T2DM);DMnDE,with T2DM not having dry eyes;DEnDM,with dry eyes not having diabetes;and nDMnDE,with neither dry eyes nor *** tear film break-up time,Schirmer I test,in vivo confocal microscopy,and BR were *** The DEwDM,DMnDE,DEnDM,and nDMnDE groups included 56,22,33,and 20 patients,*** and age were not statistically different among the four *** nerve fiber length(NFL)of patients in the DEwDM,DEnDM,and DMnDE groups reduced(P<0.001,P=0.014,and P=0.001,respectively).No significant difference in corneal nerve fiber density(NFD)(P=0.083)and corneal nerve branch density(NBD)(P=0.195)was found among the four *** R1 Latency of blink reflexes increased only in the DEwDM group(P=0.008,P=0.001,P<0.001,compared with the DMnDE,DEnDM,and nDMnDE groups,respectively).The NBD and R1 Latency were different between DEwDM and DEnDM groups in patients with moderate and severe dry *** The corneal nerve morphology changed in patients with dry eyes or diabetes,or

关键词： Blink reflex Corneal nerve Diabetes mellitus Dry eye Tear secretion