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Enhanced service stability and thermoelectric performance in Cu_(2)−δSebased composites

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Science China Materials 2024年第7期67卷 2369-2370页

作者： Pengfei qiu Xun Shi State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China

Thermoelectric(TE)materials can directly convert the industrial waste heat into useful electricity based on the Seebeck effect,providing a promising way to tackle the environmental pollution and global energy crisis[1].In the past several decades,many new high-performance TE materials have been discovered to enrich the TE *** them,Cu_(2)−δSe-based TE materials,which are in line with the“phonon-liquid electron-crystal”concept,have sparked widespread interest due to the high TE figure-of-merit(ZT)and the combination of elements that are nontoxic and earth-abundant[2].In 2012,Liu et al.[3]reported a ZT of 1.5 at 1000 K in the stoichiometric Cu_(2)*** alloying S at the Se-site,the ZT was enhanced to around 2.0 at 1000 K[4].Via incorporating carbon nanotubes,the ZT was further enhanced to 2.4 at 1000 K[5].Moreover,Yang et al.[6]and Zhou et al.[7]reported that the ZT of Cu_(2)Se/BiCuSeO composites can reach 2.7–2.8 around 1000 K.

关键词： composites BiCuSeO performance

Prevalence and risk factors of depression among patients with perianal fistulizing Crohn’s disease

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World Journal of Psychiatry 2024年第5期14卷 715-725页

作者： Jing Li Wing-Yi ng Li-Chao Qiao Fen Yuan Xing Lan Li-Bei Zhu Bo-Lin Yang Zhong-qiu Wang Department of Radiology Jiangsu Province Hospital of Chinese Medicine Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina Department of Acupuncture and Rehabilitation Jiangsu Province Hospital of Chinese Medicine Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina Department of Colorectal Surgery Jiangsu Province Hospital of Chinese Medicine Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210029Jiangsu ProvinceChina

BACKGROUND Psychological distress,especially depression,associated with perianal fistulizing Crohn’s disease(PFCD)is widespread and ***,there is a surprising paucity of studies to date that have sought to identify the prevalence and risk factors of depression associated with *** To estimate the prevalence of depressive symptoms and investigate the depression-related risk factors in patients with *** The study was conducted in the form of survey and clinical data collection via questionnaire and specialized medical *** symptoms,life quality,and fatigue severity of patients with PFCD were assessed by Patient Health Questionnaire-9,Inflammatory Bowel Disease Patient Quality of Life Questionnaire(IBDQ),and Inflammatory Bowel Disease(IBD)Fatigue Patient Self-assessment *** basic demographic information,overall disease features,perianal clinical information,and laboratory inflammation indicators were also *** regression analysis was ultimately used to ascertain the risk factors of depression associated with *** A total of 123 patients with PFCD were involved,and 56.91%were suffering from *** to multivariate logistic regression analysis,Perianal Disease Activity Index(PDAI)score[odds ratio(OR)=0.69,95%confidence interval(CI):0.50 to 0.95],IBDQ score(OR=0.93,95%CI:0.88 to 0.97),modified Van Assche index(OR=1.24,95%CI:1.01 to 1.53),and IBD Fatigue score(OR=1.72,95%CI:1.23 to 2.42)were independent risk factors of depression-related prevalence among patients with PFCD(Png perianal modified Van Assche index(βvalue=0.166,95%CI:0.02 to 0.31)and decreasing IBDQ score(βvalue=-0.116,95%CI:-0.14 to-0.09)were independently associated with the severity of depression(P<0.05).CONCLUSION Depressive symptoms in PFCD patients have significantly high *** score,modified Van Assche index,quality of life,and fatigue severity

关键词： Crohn’s disease Fistula Depression Inflammatory bowel diseases Risk factors

Effect of Modulus Heterogeneity on the Equilibrium Shape and Stress Field ofαPrecipitate in Ti-6Al-4V

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 1017-1028页

作者： Di qiu Rongpei Shi Materials Genome Institute Shanghai UniversityShanghai200444China School of Materials Science and Engineering Harbin Institute of TechnologyShenzhen518055China Shanghai Frontier Science Center of Mechanoinformatics Shanghai UniversityShanghai200444China Zhejiang Laboratory Hangzhou311100China

For media with inclusions(e.g.,precipitates,voids,reinforcements,and others),the difference in lattice parameter and the elastic modulus between the matrix and inclusions cause stress concentration at the *** stress fields depend on the inclusions’size,shape,and distribution and will respond instantly to the evolving *** study develops a phase-field model concerningmodulus *** effect of modulus heterogeneity on the growth process and equilibrium state of theαplate in Ti-6Al-4V during precipitation is ***αprecipitate exhibits strong anisotropy in shape upon cooling due to the interplay of the elastic strain and interfacial *** calculated orientation of the habit plane using the homogeneous modulus ofαphase shows the smallest deviation fromthat of the habit plane observed in the experiment,compared to the case where the homogeneous modulus ofβphase is *** addition,the equilibrium volume ofαphase within the systemusing homogeneousβmodulus exhibits the largest dependency on the applied *** stress fields across theα/βinterface are further calculated under the assumption of modulus heterogeneity and compared to those using homogeneous modulus of eitherαorβ*** study provides an essential theoretical basis for developing mechanics models concerning systems with heterogeneous structures.

关键词： Elastic heterogeneity habit plane stress field titanium phase-field simulation

An oscillation-free Hermite WENO scheme for hyperbolic conservation laws

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Science China Mathematics 2024年第2期67卷 431-454页

作者： Zhuang Zhao Jianxian qiu School of Mathematical Sciences and Institute of Natural Sciences Shanghai Jiao Tong UniversityShanghai 200240China School of Mathematical Sciences and Fujian Provincial Key Laboratory of Mathematical Modeling and High-Performance Scientific Computing Xiamen UniversityXiamen 361005China

In this paper, the sixth-order oscillation-free Hermite weighted essentially non-oscillatory (OFHWENO) scheme is proposed for hyperbolic conservation laws on structured meshes, where the zeroth- andfirst-order moments are the variables for the governing equations. The main difference from other HWENOschemes existing in the literature is that we add high-order numerical damping terms in the first-order momentequations to control spurious oscillations for the OF-HWENO scheme. The OF-HWENO scheme not only canachieve the designed optimal numerical order, but also can be easily implemented as we use only one set ofstencils in the reconstruction procedure and the same reconstructed polynomials are applied for the zeroth- andfirst-order moment equations. In order to obtain the adaptive order resolution when facing discontinuities, atransition polynomial is added in the reconstruction, where the associated linear weights can also be any positivenumbers as long as their summation equals one. In addition, the OF-HWENO scheme still keeps compactnessas only immediate neighbor values are needed in the space discretization. Some benchmark numerical tests areperformed to illustrate the high-order accuracy, high resolution and robustness of the proposed scheme.

关键词： Hermite WENO scheme hyperbolic conservation laws oscillation-free adaptive order discontinuous Galerkin method

Carbon enhanced nucleophilicity of Na_(3)V_(2)(PO_(4))_(3):A general approach for dendrite-free zinc metal anodes

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Journal of Energy Chemistry 2024年第4期91卷 203-212页

作者： Sijun Wang Lingzi Hu Xiaohui Li Dan qiu Shunhang qiu Qiancheng Zhou Wenwen Deng Xiaoying Lu Ze Yang Ming qiu Ying Yu Institute of Nanoscience and Nanotechnology School of Physical Science and TechnologyCentral China Normal UniversityWuhan 430079HubeiChina School of Material Science and Engineering Suzhou University of Science and TechnologySuzhou 215000JiangsuChina Faculty of Science and Technology Technological and Higher Education Institute of Hong KongHong KongChina

Zincophilic property and high electrical conductivity are both very important parameters to design novel Zn anode for aqueous Zn-ion batteries(AZIBs).However,single material is difficult to exhibit zincophilic property and high electrical conductivity at the same ***,originating from theoretical calculation,a zincophilic particle regulation strategy is proposed to address these limitations and carbon coated Na_(3)V_(2)(PO_(4))_(3)is taken as an example to be a protective layer on zinc metal(NVPC@Zn).Na_(3)V_(2)(PO_(4))_(3)(NVP)is a common cathode material for Zn-ion batteries,which is *** materials not only offer an electron pathway to help Zn deposition onto NVPC surface,but also enhance the zinc nucleophilicity of Na_(3)V_(2)(PO_(4))_(3).Hence,this hybrid coating layer can tune zinc deposition and resist side reactions such as hydrogen generation and Zn metal ***,a symmetrical battery with NVPC@Zn electrode displays highly reversible plating/stripping behavior with a long cycle lifespan over 1800 h at2 mA cm^(-2),much better than carbon and Na_(3)V_(2)(PO_(4))_(3)solely modified Zn *** the Na_(3)V_(2)(PO_(4))_(3)is replaced with zincophobic Al2O3or zincophilic V2O3,the stability of the modified zinc anodes is also *** strategy expands the option of zincophilic materials and provides a general and effective way to stabilize the Zn electrode.

关键词： Zinc-ion batteries Zinc anode Carbon enhanced nucleophilicity Zincophilic particle regulation

Tensor perturbations from bounce inflation scenario in f(Q)gravity

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 78-92页

作者： Kun Hu Tanmoy Paul Taotao qiu Institute of Astrophysics Central China Normal UniversityWuhan 430079China School of Physics Huazhong University of Science and TechnologyWuhan 430074China National Institute of Technology Jamshedpur Department of PhysicsJamshedpur 831014India

In this paper,we construct a bounce inflation cosmological scenario in the framework of the modified symmetric teleparallel gravity,namely f(Q)theory,and investigate the tensor perturbations *** is well-known,the tensor perturbations generated in the very early Universe(inflation and pre-inflation regions)can account for the primordial gravitational waves(PGWs)that are to be detected by the next generation of GW *** discuss the stability condition of the tensor perturbations in the bounce inflation process and investigate in detail the evolution of the perturbation *** general form of the tensor power spectrum is obtained both for large as well as small scale *** a result,we show both kinds of modes(short or long wavelength modes),and the tensor spectrum may get a positive tilt in the parametric range where the tensor perturbation proves to be stable—this interestingly hints an enhancement of gravitational waves’amplitude in the background of the f(Q)bounce-inflation ***,we study the LQC-like scenario as a specific case of our model,in which,the primordial tensor power spectrum turns out to be nearly scale-invariant on both small and large scales.

关键词： bounce cosmology modified gravity cosmological perturbations

Model-driven path planning for robotic plasma cutting of branch pipe with single Y-groove based on pipe-rotating scheme

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Advances in Manufacturing 2024年第1期12卷 94-107页

作者： Yan Liu qiu Tang Xin-Cheng Tian School of Control Science and Engineering Shandong UniversityJinan250061People’s Republic of China Engineering Research Center of Intelligent Unmanned System Ministry of EducationJinan250061People’s Republic of China School of Mechanical and Electronic Engineering Shandong Jianzhu UniversityJinan250101People’s Republic of China

The automatic cutting of intersecting pipes is a challenging task in *** improved automation and accuracy,this paper proposes a model-driven path planning approach for the robotic plasma cutting of a branch pipe with a single ***,it summarizes the intersection forms and introduces a dual-pipe intersection *** on this model,the moving three-plane structure(a description unit of the geometric characteristics of the intersecting curve)is constructed,and a geometric model of the branch pipe with a single Y-groove is ***,a novel mathematical model for plasma radius and taper compensation is ***,the compensation model and groove model are integrated by establishing movable ***,to prevent collisions between the plasma torch and workpiece,the torch height is planned and a branch pipe-rotating scheme is *** the established models and moving frames,the planned path description of cutting robot is provided in this novel *** accuracy of the proposed method is verified by simulations and robotic cutting experiments.

关键词： Automatic groove cutting of intersecting pipes Model-driven robot path planning Plasma beam radius and taper compensation

Effect of Calcination Temperature on the Microstructure and Surface Properties of a Cu/ZnO Catalyst Derived from Zn_(3)Cu_(2)(OH)_(6)(CO_(3))_(2)

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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

Dimension by Dimension Finite Volume HWENO Method for Hyperbolic Conservation Laws

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Communications on Applied Mathematics and Computation 2024年第1期6卷 605-624页

作者： Feng Zheng Jianxian qiu College of Mathematics and Statistics Fujian Normal UniversityFuzhou350117FujianChina School of Mathematical Sciences and Fujian Provincial Key Laboratory of Mathematical Modeling&High-Performance Scientific Computing Xiamen UniversityXiamen361005FujianChina

In this paper,we propose a finite volume Hermite weighted essentially non-oscillatory(HWENO)method based on the dimension by dimension framework to solve hyperbolic conservation *** can maintain the high accuracy in the smooth region and obtain the high resolution solution when the discontinuity appears,and it is compact which will be good for giving the numerical boundary ***,it avoids complicated least square procedure when we implement the genuine two dimensional(2D)finite volume HWENO reconstruction,and it can be regarded as a generalization of the one dimensional(1D)HWENO *** numerical tests are performed to verify the high resolution and high accuracy of the scheme.

关键词： Finite volume Dimension by dimension HWENO Hyperbolic conservation laws