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Metal-free phthalocyanine single crystal： Solvothermal synthesis and near-infrared electroluminescence

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Chinese Chemical Letters 2016年第5期27卷 764-768页

作者： Qing-Long Bai chun-Hua Zhang Juan-Juan song Jing-Hai Liu Yan-chun Feng Li-Mei Duan Chuan-Hui cheng Inner Mongolia Key Lab of Chemistry of Natural Products and Synthesis of Functional Molecules College of Chemistry and Chemical Engineering Inner Mongolia University for Nationalities Tongliao 028000 China School of Physics and Optoelectronics Technology Dalian University of Technology Dalian 116024 China

A metal-flee purple H2Pc single crystal was synthesized by a facile solvothermal method, and its solubility and near-infrared （NIR） optical properties were also investigated due to its potential applications as a light-emitting layer for OLEDs. The H2Pc single crystal is insoluble in 1-chlorine naphthalene and other organic solvents. It gives a wide absorption in the range from 620 nm to 679 nm and a wide emission in near 922 nm. As an active light-emitting layer, H2Pc was employed to fabricate electroluminescent （EL） devices with a structure of ITO/NPB （30 nm）/Alq3：H2Pc （30 nm）/BCP （20 nm）/ Alq3 （20 nm）/Al. The emission center is at 936 nm when the H2Pc doping concentration is 20 wt%. The doping concentration strongly governs the emission intensity. When doping concentration decreases from 10 wt% to 1 wt%, the emission intensity remarkably fades, and simultaneously the emission center undergoes a blue shift.

关键词： Solvothermal synthesis H2Pc single crystal Optical properties Near-infrared Electroluminescence

Development of a MCNP5 and ORIGEN2 based burnup code for molten salt reactor

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Nuclear Science and Techniques 2016年第3期27卷 108-114页

作者： Guo-Min Sun Mao-song cheng Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

The Molten Salt Reactor(MSR) is one of the six advanced reactor nuclear energy systems for further research and development selected by Generation IV International Forum(GIF),which is distinguished by its core in which the fuel is dissolved in molten fluoride *** fuel flow in the primary loop,the depletion of MSR is different from that of solid-fuel *** this paper,an MCNP5 and ORIGEN2 Coupled Burnup(MOCBurn) code for MSR is developed under the MATLAB *** new methods and novel arrangements are used to make it suitable for fuel flow in the *** consider the fuel convection and diffusion in the primary loop of MSR,fuel mixing calculation is carried out after each burnup time *** function for geometry with repeat structures is implicated for reactor analysis with complex *** for a high-burnup reactor pin cell benchmark is performed using the MOCBurn *** of depletion study show that the MOCBurn code is suitable for the traditional solid-fuel reactors.A preliminary study of the fuel mixture effect in MSR is also carried out.

关键词：程序开发高燃耗熔盐堆 MATLAB平台先进反应堆固体燃料重复结构 MSR

Effect of modified carrier fluoride on the performance of Ni–Mo/Al2O3 catalyst for thioetherification

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Petroleum Science 2020年第3期17卷 849-857页

作者： Zhao Han Zhuang Ma cheng-Bo Wang chun-Yu He Ming Ke Qing-Zhe Jiang Zhao-Zheng song College of Science China University of PetroleumBeijing 102249China PetroChina Beijing Marketing Company Beijing 100101China

An alumina support was modified by fluorine via impregnation to investigate the effect of fluoride content on the reactivity of Ni–Mo/Al2O3 *** catalyst was characterized by X-ray diffraction,N2 adsorption–desorption(Brunauer–Emmett–Teller)isotherms,temperature-programmed desorption of ammonia,X-ray photoelectron spectroscopy and high-resolution transmission electron *** etherification performance of the catalyst was studied using a fixed-bed *** results show that increasing fluoride content increases the pore volume and pore size but reduces the specific surface *** addition,the degree of sulfidation of Ni first increases and then *** amounts of strong acid and total acid also increase with increasing fluoride *** evaluation of the catalyst reveals that the fluoride content has a minor effect on the thioetherification performance of the catalyst;however,an optimum fluoride content,which was determined to be 0.2%,can ensure lower olefin saturation and an efficient diene selective hydrogenation.

关键词： Fluorine Thioetherification Fluorinated ammonia Selective hydrogenation NiMo/y-Al2O3

Unequal clustering algorithm for WSN based on fuzzy logic and improved ACO

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The Journal of China Universities of Posts and Telecommunications 2011年第6期18卷 89-97页

作者： MAO song ZHAO cheng-lin Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China Wireless Network Lab Beijing University of Posts and Telecommunications Beijing 100876 China

This paper proposes a novel energy efficient unequal clustering algorithm for large scale wireless sensor network （WSN） which aims to balance the node power consumption and prolong the network lifetime as long as possible. Our approach focuses on energy efficient unequal clustering scheme and inter-cluster routing protocol. On the one hand, considering each node＇s local information such as energy level, distance to base station and local density, we use fuzzy logic system to determine one node＇s chance of becoming cluster head and hand, adaptive max-min ant colony optimization is used to estimate the corresponding competence radius. On the other construct energy-aware inter-cluster routing between cluster heads and base station （BS）, which balances the energy consumption of cluster heads and alleviates the hot spots problem that occurs in multi-hop WSN routing protocol to a large extent. The confirmation experiment results have indicated the proposed clustering algorithm has more superior performance than other methods such as low energy adaptive clustering hierarchy （LEACH） and energy efficient unequal clustering （EEUC）.

关键词： WSN unequal clustering fuzzy logic adaptive max-min ant colony optimization (ACO) network lifetime

Riemann Problem for a Geometrical Optics System

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Acta Mathematica Sinica,English Series 2014年第11期30卷 1846-1860页

作者： Han chun YANG Hong Jun cheng Department of Mathematics Yunnan University

The paper solves analytically the Riemann problem for a nonstrictly hyperbolic system of conservation laws arising in geometrical optics,in which the flux contains the nonconvex function possessing an infinite number of inflection ***,the generalized Rankine–Hugoniot relations and entropy condition of delta shock waves and left（right）-contact delta shock waves are proposed and ***,with the help of the convex hull,seven kinds of structures of Riemann solutions are *** solutions fall into three broad categories with a series of geometric structures involving simultaneously contact discontinuities,vacuums and delta shock ***,numerical experiments confirm the theoretical analysis.

关键词： Geometrical optics Riemann problem delta shock wave vacuum convex hull

Some notes on a conjecture of Zygmund

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Applied Mathematics(A Journal of Chinese Universities) 2008年第2期23卷 213-218页

作者： CHEN Jie-cheng ZHANG chun-jie Dept. of Math. Zhejiang Univ. Hangzhou 310027 China

In this paper, some classes of differentiation basis are investigated and several positive answers to a conjecture of Zygmund on differentiation of integrals are presented.

关键词： Zygmund's conjecture differentiation of integrals maximal function.

Monthly discharge forecasting using wavelet neural networks with extreme learning machine

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Science China(Technological Sciences) 2014年第12期57卷 2441-2452页

作者： LI Bao Jian cheng chun Tian Institute of Hydropower System and Hydroinformatics Dalian University of Technology

Accurate and reliable hydrological forecasting is essential for water resource management. Feedforward neural networks can provide satisfactory forecast results in most cases, but traditional gradient-based training algorithms are usually time-consum- ing and may easily converge to local minimum. Hence, how to obtain more appropriate parameters for feedforward neural networks with more precise prediction within shorter time has been a challenging task. Extreme learning machine （ELM）, a new training algorithm for single-hidden layer feedforward neural networks （SLFNs）, has been proposed to avoid these disad- vantages. In this study, a conjunction model of wavelet neural networks with ELM （WNN-ELM） is proposed for 1-month ahead discharge forecasting, The ~ trous wavelet transform is used to decompose the original discharge time series into several sub-series. The sub-series are then used as inputs for SLFNs coupled with ELM algorithm （SLFNs^ELM）; the output is the next step observed discharge. For comparison, the SLFNs-ELM and support vector machine （SVM） are also employed. Monthly discharge time series data from two reservoirs in southwestern China are derive] for validating the models. In addi- tion, four quantitative standard statistical performance evaluation measures are utilized to evaluate the model performance. The results indicate that the SLFNs-ELM performs slightly better than the SVM for peak discharge estimation, and the proposed model WNN-ELM provides more accurate forecast precision than SLFNs-ELM and SVM

关键词： monthly discharges discrete wavelet transform extreme learning machine forecasting

Observation of topological charge transformations in acoustic vortex using passive periodic systems

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 140-147页

作者： Di-Chao Chen Xie Liu Changqing Xu Da-Jian Wu Ying cheng Xiao-Jun Liu School of Physics and Technology Nanjing Normal University Key Laboratory of Modern Acoustics School of Physics Nanjing University

Vortex transmutation utilizes a periodic system, which not only enables the alteration of the topological charge(TC) of unstable input vortices but also facilitates their transformation into stable structures. This approach is crucial for investigating the characteristics of vortices in various wave systems. Here, we achieve acoustic vortex TC transmutation by employing a welldesigned dual-structured plate external system(DPES). The interactions between the acoustic vortex and the finite-order discrete rotational symmetry lead to the transformation of its topological charge when complete rotational symmetry is broken to Nthorder discrete symmetry. Our results experimentally demonstrate the acoustic vortex TC transmutation based on passive artificial structures, enabling numerous applications in particle manipulation and information multiplexing as well as advancing our understanding and control over free-space acoustic vortices.

关键词： acoustic vortex topological charge transformation artificial structure

Numerical Implementation of a Unified Viscoplastic Model for Considering Solder Joint Response under Board-Level Temperature Cycling

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Computer Modeling in Engineering & Sciences 2021年第8期128卷 639-668页

作者： Hung-chun Yang Tz-cheng Chiu Department of Mechanical Engineering National Cheng Kung UniversityTainan701Taiwan

An implicit integration scheme was developed for simulating the viscoplastic constitutive behavior ofSn3.0Ag0.5Cu solder and programmed into a user material subroutine of the finite element software ANSYS. Thenumerical procedure first solves the essential state variables by using a three-level iterative procedure, and updatesthe remaining stress and state variables accordingly. The numerical implementation was applied to consider theresponses of solder joints in an electronic assembly under temperature cycling condition. The viscoplastic strainenergy density accumulation over one temperature cycle was identified as a feasible parameter for evaluating thethermomechanical reliability of the solder joints.

关键词： Pb-free hysteresis ratcheting fatigue tangent modulus