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China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 46-56页

作者： Qiu Shiming Wang Shengjie School of Chemistry and Chemical Engineering Guangxi Minzu Normal UniversityChongzuo 532200GuangxiChina guangxi Key Laboratory for High-value Utilization of Manganese Resources Chongzuo 532200GuangxiChina

The Cu/ZnO catalyst formed upon the calcination of aurichalcite has a uniform distribution of ZnO,which can delay the sintering of Cu species at high *** this study,aurichalcite possessing a nearly pure phase was prepared using the ammonium complex dissociation precipitation method,and the effect of calcination temperature on the structure and surface properties of the derived Cu/ZnO catalyst was *** results show that the calcination temperature determines the particle size and crystallization degree of the Cu/ZnO catalyst and the surface properties of the corresponding copper oxide and reduced ***-temperature calcination is more conducive to reducing the particle size of the Cu/ZnO catalyst,increasing the specific surface area,and generating abundant defect characteristics on the surface,which is key to obtaining highly dispersed copper and copper-specific surface area catalysts by subsequent ***,the Cu/ZnO catalyst derived using a 300℃or 400℃calcination proved to have a higher specific activity per gram of copper than a commercial Cu/Zn/Al *** discovery in this study opens up a new method for the convenient preparation of a high-temperature resistant Cu/Zn methanol reforming catalyst.

关键词： methanol reforming copper zinc oxide lattice defect

Parametric“non-nested”discriminants for multiplicities of univariate polynomials

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Science China Mathematics 2024年第8期67卷 1911-1932页

作者： Hoon Hong Jing Yang Department of Mathematics North Carolina State UniversityRaleighNC 27695USA SMS-HCIC-School of Mathematics and Physics Center for Applied Mathematics of GuangxiGuangxi Minzu UniversityNanning 530006China

We consider the problem of complex root classification,i.e.,finding the conditions on the coefficients of a univariate polynomial for all possible multiplicity structures on its complex *** is well known that such conditions can be written as conjunctions of several polynomial equalities and one inequality in the *** polynomials in the coefficients are called discriminants for *** is also known that discriminants can be obtained using repeated parametric greatest common *** resulting discriminants are usually nested determinants,i.e.,determinants of matrices whose entries are determinants,and so *** this paper,we give a new type of discriminant that is not based on repeated greatest common *** new discriminants are simpler in the sense that they are non-nested determinants and have smaller maximum degrees.

关键词： parametric polynomial complex roots discriminant multiplicity resultant

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Differential Evolution Hemivariational Inequalities with Anti-periodic Conditions

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Acta Mathematica Sinica,English Series 2024年第4期40卷 1143-1160页

作者： Jing ZHAO Chun Mei GAN Zhen Hai LIU School of Mathematics and Quantitative Economics Guangxi University of Finance and EconomicsNanning 530003P.R.China guangxi Colleges and Universities Key Laboratory of Optimization Control and Engineering Calculation Guangxi Minzu UniversityNanning 530006P.R.China

The goal of this paper is to deal with a new dynamic system called a differential evolution hemivariational inequality(DEHVI)which couples an abstract parabolic evolution hemivariational inequality and a nonlinear differential equation in a Banach ***,by apply ing surjectivity result for pseudomonotone multivalued mappins and the properties of Clarke's subgradient,we show the nonempty of the solution set for the parabolic hemivariational ***,some topological properties of the solution set are established such as boundedness,closedness and ***,we explore the upper semicontinuity of the solution ***,we prove the solution set of the system(DEHVI)is nonempty and the set of all trajectories of(DEHVI)is weakly compact in C(I,X).

关键词： Differential parabolic hemivariational inequality Clarke subdifferential hyperbolicparabolic system parabolic-parabolic system existence result

Reduced exciton binding energy and diverse molecular stacking enable high-performance organic solar cells with VOC over 1.1 V

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Science China Chemistry 2024年第9期67卷 3140-3152页

作者： Tingting Dai Jiahao Lu Ailing Tang Yuhan Meng Peiqing Cong Zongtao Wang Erjun Zhou National Center for Nanoscience and Technology Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences College of Chemistry and Chemical Engineering Guangxi Minzu University Henan Institute of Advanced Technology Zhengzhou University

High-voltage organic solar cells（OSCs） have received increasing attention because of their promising applications in tandem devices and indoor photovoltaics, but the trade-off between energy loss and charge generation induced by exciton binding energy（Eb） has become one of the biggest bottlenecks limiting the development of this field. Here, a wide bandgap（WBG） nonfullerene acceptor BTA503 with reduced Ebis designed by changing the phenyl side chain on the central core of Cl-BTA5 to an alkyl chain. The diverse π-π interactions and enhanced molecular stacking of BTA503 are responsible for its reduced ***, both the diminished charge recombination and the fast exciton dissociation caused by the small Ebfavor the generation of more charge carriers for the PTQ10:BTA503 combination. The efficient F?rster resonance energy transfer（FRET）and multiple π-π stacking patterns provide additional charge transfer and transport pathways. Ultimately, the PTQ10:BTA503-based OSC device achieves a VOCof 1.112 V and a PCE of 12.70%, which is higher than that of PTQ10:Cl-BTA5（PCE=10.92%）. Simultaneously, the thick film（～300 nm） binary device of PTQ10:BTA503 achieves a PCE of 10.13% with a VOCof 1.102 V, which is the best result for thick film high-voltage OSCs. More importantly, the ternary device of PTQ10:BTA503:Cl-BTA5（1:0.9:0.1） realizes a champion PCE of 13.12% with a VOCof 1.126 V. Our study demonstrates that it is an effective strategy to reduce Ebof A2-A1-D-A1-A2type WBG acceptors by modulating the side chains on D unit, which further favors the corresponding devices to obtain world-record PCE and improves their potential for commercial applications.

关键词： exciton binding energy intermolecular interaction wide-bandgap acceptor high VOC organic solar cells

A Bregman-Style Improved ADMM and its Linearized Version in the Nonconvex Setting:Convergence and Rate Analyses

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Journal of the Operations Research Society of China 2024年第2期12卷 298-340页

作者： Peng-Jie Liu Jin-Bao Jian Hu Shao Xiao-Quan Wang Jia-Wei Xu Xiao-Yu Wu School of Mathematics Jiangsu Center for Applied MathematicsChina University of Mining and TechnologyXuzhou 221116JiangsuChina School of Mathematics and Physics Center for Applied Mathematics of GuangxiGuangxi Minzu UniversityNanning 530006GuangxiChina Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong KongChina School of Mathematics and Computational Science Xiangtan UniversityXiangtan 411105HunanChina

This work explores a family of two-block nonconvex optimization problems subject to linear *** first introduce a simple but universal Bregman-style improved alternating direction method of multipliers(ADMM)based on the iteration framework of ADMM and the Bregman ***,we utilize the smooth performance of one of the components to develop a linearized version of *** to the traditional ADMM,both proposed methods integrate a convex combination strategy into the multiplier update *** each proposed method,we demonstrate the convergence of the entire iteration sequence to a unique critical point of the augmented Lagrangian function utilizing the powerful Kurdyka–Łojasiewicz property,and we also derive convergence rates for both the sequence of merit function values and the iteration ***,some numerical results show that the proposed methods are effective and encouraging for the Lasso model.

关键词： Nonconvex optimization Alternating direction method of multipliers:Kurdyka-Lojasiewicz property.Convergence rate

Data-driven Surrogate-assisted Method for High-dimensional Multi-area Combined Economic/Emission Dispatch

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 52-64页

作者： Chenhao Lin Huijun Liang Aokang Pang Jianwei Zhong Yongchao Yang the College of Intelligent Systems Science and Engineering Hubei Minzu UniversityEnshiChina

Multi-area combined economic/emission dispatch(MACEED)problems are generally studied using analytical ***,as the scale of power systems increases,ex isting solutions become time-consuming and may not meet oper ational *** overcome excessive computational ex pense in high-dimensional MACEED problems,a novel data-driven surrogate-assisted method is ***,a cosine-similarity-based deep belief network combined with a back-propagation(DBN+BP)neural network is utilized to replace cost and emission ***,transfer learning is applied with a pretraining and fine-tuning method to improve DBN+BP regression surrogate models,thus realizing fast con struction of surrogate models between different regional power ***,a multi-objective antlion optimizer with a novel general single-dimension retention bi-objective optimization poli cy is proposed to execute MACEED optimization to obtain scheduling *** proposed method not only ensures the convergence,uniformity,and extensibility of the Pareto front,but also greatly reduces the computational ***,a 4-ar ea 40-unit test system with different constraints is employed to demonstrate the effectiveness of the proposed method.

关键词： Multi-area combined economic/emission dispatch high-dimensional power system deep belief network data driven transfer learning

ρ-meson longitudinal leading-twist distribution amplitude revisited and the D→ρsemileptonic decay

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Chinese Physics C 2024年第6期48卷 82-91页

作者：钟涛代亚红付海冰 Department of Physics Guizhou Minzu UniversityGuiyang 550025China

Motivated by our previous study[***.D 104(1),016021(2021)]on the pionic leading-twist distribution amplitude(DA),we revisit theρ-me son leading-twist longitudinal DAφ_(2;ρ)^(‖)(x,μ)in this study.A model proposed by Chang based on the DYyson-Schwinger equations is adopted to describe the behavior ofφ_(2;ρ)^(‖)(x,μ).However,theξ-moments ofφ_(2;ρ)^(‖)(x,μ)are calculated with the QCD sum rules in the framework of the background field *** sum rule formulas for these moments are *** accurate values for the first five nonzeroξ-moments at the typical scaleμ=(1.0,1.4,2.0,3.0)GeV are given,e.g.,atμ=1 GeV,(ξ^(2))>_(2;ρ)^(‖)=0.220(6),(ξ^(4))>_(2;ρ)^(‖)=0.103(4),(ξ^(6))>_(2;ρ)^(‖)=0.066(5),(ξ^(8))>_(2;ρ)^(‖)=0.046(4),and(ξ^(10))>_(2;ρ)^(‖)=0.035(3).By fitting these values with the least squares method,the DSE model forφ_(2;ρ)(x,μ)is *** taking the left-handed current light-cone sum rule approach,we obtain the transition form factor in the large recoil region,i.e.,A_(1)(0)=0.498_(-0.012)^(+0.014),A_(2)(0)=0.460_(-0.047)^(+0.055),and V(0)=0.800_(-0.014)^(+0.015),and the ratio r_(2)=0.923_(-0.119)^(+0.133),rV=1.607_(-0.071)^(+0.071).After extrapolating with a rapidly converging series based on z(t)-expansion,we present the|V_(cd)|-independent decay width for the semileptonic decays D→ρ^(l+)v_(l).Finally,the branching fractions are B(D^(0)→ρ^(-)e+v_(e))=1.825_(-0.162)^(+0.170)±0.004,B(D^(+)→ρ^(0)e+v_(e))=2.299_(-0.204)^(+0.214)±0.011,B(D^(0)→ρ^(-)μ^(+)v_(μ))=1.816_(-0.160)^(+0.168)±0.004,and B(D^(+)→ρ^(0)μ+v_(μ))=2.288_(-0.201)^(+0.212)±0.011.

关键词： QCD sum rule charmed meson semileptonic decay Rho meson light-cone distribution amplitude

Image Inpainting Technique Incorporating Edge Prior and Attention Mechanism

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Computers, Materials & Continua 2024年第1期78卷 999-1025页

作者： Jinxian Bai Yao Fan Zhiwei Zhao Lizhi Zheng College of Information Engineering Xizang Minzu UniversityXianyang712000China

Recently,deep learning-based image inpainting methods have made great strides in reconstructing damaged ***,these methods often struggle to produce satisfactory results when dealing with missing images with large holes,leading to distortions in the structure and blurring of *** address these problems,we combine the advantages of transformers and convolutions to propose an image inpainting method that incorporates edge priors and attention *** proposed method aims to improve the results of inpainting large holes in images by enhancing the accuracy of structure restoration and the ability to recover texture *** method divides the inpainting task into two phases:edge prediction and image ***,in the edge prediction phase,a transformer architecture is designed to combine axial attention with standard *** design enhances the extraction capability of global structural features and location *** also balances the complexity of self-attention operations,resulting in accurate prediction of the edge structure in the defective *** the image inpainting phase,a multi-scale fusion attention module is *** module makes full use of multi-level distant features and enhances local pixel continuity,thereby significantly improving the quality of image *** evaluate the performance of our *** experiments are conducted on several datasets,including CelebA,Places2,and *** experiments show that our method outperforms the other mainstream ***,it improves Peak Signal-to-Noise Ratio(PSNR)and Structure Similarity Index Measure(SSIM)by 1.141~3.234 db and 0.083~0.235,***,it reduces Learning Perceptual Image Patch Similarity(LPIPS)and Mean Absolute Error(MAE)by 0.0347~0.1753 and 0.0104~0.0402,*** experiments reveal that our method excels at reconstructing images with complete structural information and c

关键词： Image inpainting transformer edge prior axial attention multi-scale fusion attention

Study on the flow structure in curved open channels with suspended vegetation using multi relaxation time lattice Boltzmann method

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Journal of Hydrodynamics 2024年第2期36卷 300-315页

作者： He-fang Jing Qiao-ling Zhang Wei-hong Wang Zong-ning Zhang School of Mathematics and Information Science North Minzu UniversityYinchuan750021China School of Civil Engineering North Minzu UniversityYinchuan750021China Department of Basic Courses Zhengzhou University of Science and TechnologyZhengzhou450064China

Suspended vegetation in rivers,lakes,reservoirs and canals can change flow structure,which will in turn affect the sediment transport and cause the variation of water ecological *** order to study the characteristics of bend flow through suspended vegetation,three-dimensional numerical simulations are carried out by using the multi-relaxation-time lattice Boltzmann method(MRT-LBM).The drag force induced by vegetation is added in the velocity correction in the equilibrium distribution and a hybrid format combined bounce and specular reflection scheme is applied in the solid-fluid *** the validation of this model,six cases are designed to conduct the numerical simulations according to the root depth and the arrangement of *** simulated results show that the suspended vegetation can redistribute the flow structure in curved open *** the arrangement of suspended vegetation,the main flow moves to the side without vegetation,and the distribution of velocity tends to be balanced when vegetation is arranged on the entire cross section,the range of circulating current is reduced from the whole cross section to the local position without vegetation,however,the circulating current can still exist in the curve where the suspended vegetation enters less than half of the water *** addition,it can also be concluded that the suspended vegetation can affect the lateral gradient of flow velocity,and the bed shear stress in the curved channel.

关键词： Multi-relaxation-time lattice Boltzmann method(MRT-LBM) suspended vegetation curved open channel circulating current bed shearstress

Existence of Positive Solutions to a Fractional-Kirchhoff System

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 225-240页

作者： Peng-fei Li Jun-hui Xie Dan Mu School of Mathematics and Statistics Hubei Minzu UniversityEnshi445000China

LetΩbe a bounded smooth domain in RN(N≥3).Assuming that 00 are constants,we consider the existence results for positive solutions of a class of fractional elliptic system below,{(a+b[u]^(2)_(s))(-Δ)^(s)u=vp+h_(1)(x,u,v,▽u,▽v),x∈Ω,(-Δ)^(s)v=u^(q)+h_(2)(x,u,▽,▽u,▽v),x∈Q,u,v>0,x∈Ω,u=v=0,x∈RN\Ω.Under some assumptions of hi(x,u,v,▽u,▽v)(i=1,2),we get a priori bounds of the positive solutions to the problem(1.1)by the blow-up methods and rescaling *** on these estimates and degree theory,we establish the existence of positive solutions to problem(1.1).

关键词： fractional-Kirchhoff system a priori bounds degree theory positive solution