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Chinese Physics B 2022年第5期31卷 180-188页

作者： Zhenxiong nie yun Liu Juhua Chen Yongjiu Wang Department of Physics Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of Educationand Synergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal UniversityChangsha 410081China

The thermodynamics of Bardeen black hole surrounded by perfect fluid dark matter is *** calculate the analytical expresses of corresponding thermodynamic variables,e.g.,the Hawking temperature,entropy of the black *** addition,we derive the heat capacity to analyze the thermal stability of the black *** also compute the rate of emission in terms of photons through *** numerical method,an obvious phase transition behavior is ***,according to the general uncertainty principle,we study the quantum corrections to these thermodynamic quantities and obtain the quantum-corrected entropy containing the logarithmic ***,we investigate the effects of the magnetic charge g,the dark matter parameter k and the generalized uncertainty principle parameterαon the thermodynamics of Bardeen black hole surrounded by perfect fluid dark matter under general uncertainty principle.

关键词： general uncertainty principle quantum-corrected entropy phase transition

Hysteretic behavior of cambered surface steel tube damper:Theoretical and experimental research

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Frontiers of Structural and Civil Engineering 2023年第4期17卷 606-624页

作者： Jiale LI yun ZHOU Zhiming HE Genquan zhong Chao ZHANG Department of Civil Engineering Guangzhou UniversityGuangzhou 510006China Department of Civil&Transportation Engineering Guangdong University of TechnologyGuangzhou 510006China

A novel cambered surface steel tube damper(CSTD)with a cambered surface steel tube and two concave connecting plates is proposed *** steel tube is the main energy dissipation component and comprises a weakened segment in the middle,a transition segment,and an embedded *** is believed that during an earthquake,the middle weakened segment of the CSTD will be damaged,whereas the reliability of the end connection is *** and experimental studies are conducted to verify the effectiveness of the proposed *** for the initial stiffness and yield force of the CSTD are ***,two CSTD specimens with different steel tube thicknesses are fabricated and tested under cyclic quasi-static *** result shows that the CSTD yields a stable hysteretic response and affords excellent energy dissipation.A parametric study is conducted to investigate the effects of the steel tube height,diameter,and thickness on the seismic performance of the *** with equalstiffness design steel tube dampers,the CSTD exhibits better energy dissipation performance,more stable hysteretic response,and better uniformity in plastic deformation distributions.

关键词： cambered surface steel tube damper energy dissipation capacity finite element model hysteretic performance parametric study

Stochastic Resonance-Like and Resonance Suppression-Like Phenomena in a Bistable System with Time Delay and Additive Noise

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Chinese Physics Letters 2012年第5期29卷 63-66页

作者： SHU Chang-Zheng nie Lin-Ru ZHOU zhong-Rao Faculty of Science Kunming University of Science and TechnologyKunming 650093

Stochastic resonance (SR)-like and resonance suppression (RS)-like phenomena in a time-delayed bistable system driven by additive white noise are investigated by means of stochastic simulations of the power spectrum,the quality factor of the power spectrum,and the mean first-passage time (MFPT) of the *** cal culative results indicate that:(i) as the system is driven by a small periodic signal,the quality factor as a function delay time exhibits a maximal value at smaller noise intensities,i.e.,an SR-like *** the increment in additive noise inteusity,the extremum gradually disappears and the quality factor decreases monotonously with delay time.(ii) As the additive noise intensity is smaller,the curve of the MFPT with respect to delay time displays a peak,i.e.,an RS-like *** higher levels of noise,however,the non-monotonic behavior is lost.

关键词： additive delay system

Two-Photon Absorption and Fluorescence of a Novel Compound Trans-1,3,5-tri-(4-N,N-Dimethylaminobenzylstyryl)-Acetylacetone

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Chinese Physics Letters 2001年第2期18卷 205-207页

作者： LI yun-Jing ZHAN Chuan-Lang ZHAO Li-Zeng WANG Duo-Yuan LU Zhen-zhong nie Yu-Xin Laboratory of Optical Physics Institute of PhysicsChinese Academy of SciencesBeijing 100080 The Center for Molecular Science Institute of ChemistryChinese Academy of SciencesBeijing 100080

Large two-photon absorption cross section of a novel compound trans-1,3,5-tri-(4-N,N-dimethylaminobenzylstyryl)-acetylacetone is measured to beσ_(2)=8.4×10^(-20)cm^(4)/GW orσ'_(2)=1.594×10^(-47)cm^(4)/(photon.s)by using a 1064 nm Nd:YAG laser with 35 ps pulse width based on the intensity-dependent transmissivity *** frequency upconversion fluorescence is observed by two-photon laser *** material is an ideal candidate for optical limiting and upconversion fluorescence.

关键词： measurement benzyl Fluorescence

Analysis of diffusion behavior of harmful emissions from trackless rubber-wheel diesel vehicles in underground coal mines

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International Journal of Mining Science and Technology 2022年第6期32卷 1285-1299页

作者： yun Hua Wen nie Qiang Liu Xiaofei Liu Chengyi Liu Weiwei Zhou Fengning Yu College of Safety and Environmental Engineering Shandong University of Science and TechnologyQingdao 266590China State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and TechnologyQingdao 266590China

To define the diffusion behavior of harmful exhaust substances from diesel vehicles and support safety risk assessments of underground coal mines,we performed a multi-species coupling calculation of the emission and diffusion of harmful substances from a trackless rubber-wheel diesel vehicle.A computational fluid dynamics(CFD)model of the diffusion of harmful emissions was hence established and *** the perspective of risk analysis,the diffusion behavior and distribution of hazardous substances emitted by the diesel vehicle were studied under 4 different conditions;moreover,we identified areas characterized by hazardous levels of *** the vehicle idled upwind in the roadway,high-risk areas formed behind and to the right of the vehicle:particularly high concentrations of pollutants were measured near the rear floor of the vehicle and within 5 m behind the *** the vehicle idled downwind,high-risk areas formed in front of it:particularly high concentrations of pollutants were measured near the floor and within 5 m from the front of the *** the above cases,the driver would not breathe highly polluted air and would be relatively *** the vehicle idled into the chamber,however,high-risk areas formed on both sides of the vehicle and near the upper *** entry of the vehicle caused a greater increase in the concentration of pollutants in the chamber and in the driver’s breathing zone compared with reverse entry.

关键词： Diesel vehicle Harmful emissions Diffusion behavior CFD model Underground coal mine

Individual Identification of Electronic Equipment Based on Electromagnetic Fingerprint Characteristics

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China Communications 2021年第1期18卷 169-180页

作者： Han Xu Hongxin Zhang Jun Xu Guangyuan Wang yun nie Hua Zhang School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China Beijing Aerospace Vehicle Design Department Beijing ChinaBeijing 100876China

With the rapid development of communication and computer,the individual identification technology of communication equipment has been brought to many application *** identification of the same type of electronic equipment is of considerable significance,whether it is the identification of friend or foe in military applications,identity determination,radio spectrum management in civil applications,equipment fault diagnosis,and so *** of the limited-expression ability of the traditional electromagnetic signal representation methods in the face of complex signals,a new method of individual identification of the same equipment of communication equipment based on deep learning is *** contents of this paper include the following aspects:(1)Considering the shortcomings of deep learning in processing small sample data,this paper provides a universal and robust feature template for signal *** paper constructs a relatively complete signal template library from multiple perspectives,such as time domain and transform domain features,combined with high-order statistical *** on the inspiration of the image texture feature,characteristics of amplitude histogram of signal and the signal amplitude co-occurrence matrix(SACM)are proposed in this *** signal features can be used as a signal fingerprint template for individual identification.(2)Considering the limitation of the recognition rate of a single classifier,using the integrated classifier has achieved better generalization *** final average accuracy of 5 NRF24LE1 modules is up to 98%and solved the problem of individual identification of the same equipment of communication equipment under the condition of the small sample,low signal-to-noise ratio.

关键词： signal fingerprints histogram-based signal feature starting point detection signal level cooccurrence matrix ensemble Learningn

Preparing High Silicon Steel by Sintering Fe-6.5%Si Powder Compacts in Static Magnetic Field

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Journal of Iron and Steel Research International 2012年第S1期19卷 455-458页

作者： TANG nie-wei zhong yun-bo SUN Zong-qian ZHENG Tian-xiang Shanghai Key Laboratory of Modern Metallurgy & Material Processing Shanghai University

In this research,sintering Fe-6.5wt%Si Compact specimen in static magnetic field is proposed for preparing high silicon *** is found that the densifications of the compacts are affected remarkably by superimposing magnetic *** density of the compacts can be increased when the MFD is higher than 0.2 *** highest relative density of the samples is 97.2%.The magnetic property of silicon steel could be improved when superimpose static magnetic field in sintering process,the permeability of the compact are two times of that without magnetic field,and the magnetic property parallel to the direction of the magnetic field was evidently higher than that in perpendicular direction.

关键词： 6.5wt%Si high silicon steel static magnetic field sintering orientation magnetic property

Left-definite boundary conditions of Sturm-Liouville problems when the interval shrinks to a point

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Applied Mathematics(A Journal of Chinese Universities) 2011年第1期26卷 29-37页

作者： GAO yun-lan WANG zhong WU Hong-you Department of Mathematics Inner Mongolia University of Technology Huhhot 010051 China Department of Mathematics ZhaoQing University Zhaoqing 526061 China Department of Mathematics Northern Illinois University DeKalb IL60115 USA

On the condition that the interval of the problem shrinks to a point, we investigated the separated boundary conditions Sα,β of left-definite Sturm-Liouville problem, and answered the following question： Is there a co ∈ J such that Sα,β is always left-definite or semi-left-definite for the Sturm-Liouville equation for each c ∈ （a, co）？

关键词： Left-definite Sturm-Liouville problem semi-left-definite Sturm-Liouville problem separatedboundary condition.

Enantioselective Degradation of Rac-Metolachlor and S-Metolachlor in Soil

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Pedosphere 2006年第4期16卷 489-494页

作者： MA yun LIU Wei-Ping WEN Yue-zhong Institute of Environmental Science Zhejiang University P. O. Box 31 74 Hangzhou 310029 （China） Researeh Center of Green Chirality College of Biological and Environmental Engineering Zhejiang University of Technology Hangzhou 310015 （China）

Separation of chiral enantiomers and the dissipation of rac-metolachlor and S-metolachlor in soil were evaluated using achiral high-performance liquid chromatography (HPLC) and chiral gas chromatography (GC) methods. Under the experimental conditions the possible metabolite was considered to be N-(2-ethyl-6-methyl-phenyl)-2-hydroxy-acetamide. Because of the presence of two chiral elements (asymmetrically substituted carbon and chiral axis), the baseline separation of metolachlor enantiomers was not achieved. S-metolachlor degraded faster in soil than rac-metolachlor. After a 42-day incubation, 73.4% of rac-metolachlor and 90.0% of S-metolachlor were degraded. However, due to the absence of biological processes the degradation process in sterilized soil showed no enantioselectivity. The results indicated that enantioselective degradations could greatly affect the environmental fate of metolachlor and should be considered when the environmental behavior of these compounds was assessed.

关键词： chiral separation degradation rac-metolachlor S-metolachlor soil

The Chen-Ruan Cohomology of Almost Contact Orbifolds

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Acta Mathematica Sinica,English Series 2010年第1期26卷 77-88页

作者： Fan DING yun Feng JIANG Jian zhong PAN School of Mathematics Peking University Beijing 100871 P. R. China Department of Mathematics University of Utah 155S 1400E JWB233 Salt Lake City UT 84112 USA Institute of Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 P. R. China

Comparing to the Ch-~Ruan cohomology theory for the almost complex orbifolds, we study the orbifold cohomology theory for almost contact orbifolds. We define the Chen-Ruan cohomology group of any almost contact orbifold. Using the methods for almost complex orbifolds, we define the obstruction bundle for any 3-multisector of the almost contact orbifolds and the Chen^Ruan cup product for the Che-Ruan cohomology. We also prove that under this cup product the direct sum of all dimensional orbifold cohomology groups constitutes a cohomological ring. Finally we calculate two examples.

关键词： almost contact orbifolds Chen Ruan cohomology twisted sectors almost complex orbifold