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今日中国（西文版） 2024年第2期 60-61页

作者： ZHANG aolin 不详

The symmetric space,strong isotropy irreducibility and equigeodesic properties

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Science china Mathematics 2024年第1期67卷 129-148页

作者： Ming Xu Ju tan School of Mathematical Sciences Capital Normal UniversityBeijing 100048China School of Microelectronics and Data Science Anhui University of TechnologyMa'anshan 243032China

A smooth curve on a homogeneous manifold G/H is called a Riemannian equigeodesic if it is a homogeneous geodesic for any G-invariant Riemannian *** homogeneous manifold G/H is called Riemannian equigeodesic,if for any x∈G/H and any nonzero y∈Tx(G/H),there exists a Riemannian equigeodesic c(t) with c(0)=x and ■(0)=*** two notions can be naturally transferred to the Finsler setting,which provides the definitions for Finsler equigeodesics and Finsler equigeodesic *** prove two classification theorems for Riemannian equigeodesic spaces and Finsler equigeodesic spaces,***,a homogeneous manifold G/H with a connected simply connected quasi compact G and a connected H is Riemannian equigeodesic if and only if it can be decomposed as a product of Euclidean factors and compact strongly isotropy irreducible ***,a homogeneous manifold G/H with a compact semisimple G is Finsler equigeodesic if and only if it can be locally decomposed as a product,in which each factor is Spin(7)/G2,G2/SU (3) or a symmetric space of compact *** results imply that the symmetric space and the strongly isotropy irreducible space of compact type can be interpreted by equigeodesic *** an application,we classify the homogeneous manifold G/H with a compact semisimple G such that all the G-invariant Finsler metrics on G/H are *** suggests a new project in homogeneous Finsler geometry,i.e.,to systematically study the homogeneous manifold G/H on which all the G-invariant Finsler metrics satisfy a certain geometric property.

关键词： equigeodesic equigeodesic space flag manifold orbit type stratification symmetric space strongly isotropy irreducible space

Electrical characteristics of a fractional-order 3×n Fan network

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communications in Theoretical Physics 2024年第4期76卷 176-187页

作者： Zhi-Zhong tan Xin Wang Department of Physics Nantong UniversityNantong 226019China

In this article a new achievement of fractional-order 3×n Fan networks is *** the first step,the RT-I method is used to derive the general formulae of the equivalent impedance of fractional-order 3×n Fan *** the second part,the effects of five system parameters(L,c,n,α and β)on amplitude-frequency and phase-frequency characteristics are *** the same time,the amplitude-frequency and phase-frequency characteristics of the fractional order 3×n Fan network are revealed by Matlab *** work has important theoretical and practical significance for resistor network models in the field of natural science and engineering technology.

关键词： fractional-order circuit amplitude-frequency characteristics phase-frequency characteristics RT-V theory

Enhancing visible-light-driven NO oxidation through molecular‐level insights of dye-loaded sea sands

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Rare Metals 2024年第2期43卷 543-554页

作者： Yu-Han Li Bang-Fu chen Sónia A.c.carabineiro You-Yu Duan Ping tan Wing-Kei Ho Fan Dong Engineering Research center for Waste Oil Recovery Technology and Equipment Ministry of EducationChongqing Key Laboratory of Catalysis and New Environmental MaterialsChongqing Technology and Business UniversityChongqing400067China Nanchang Institute of Technology Nanchang33044China LAQV-REQUIMTE Department of ChemistryNOVA School of Science and TechnologyUniversidade NOVA de Lisboa2829-516CaparicaPortugal college of Physics and center of Quantum Materials and Devices Chongqing UniversityChongqing401331China Department of Science and Environmental Studies The Education University of Hong KongHong Kong999077China

Natural minerals,abundant and easily obtained through simple physical processing,offer a cost-effective and environmentally friendly solution for dyeing wastewater disposal and air pollution *** study investigates the photocatalytic removal of NO using natural different types of dyes,loaded on natural sand,under visible light *** examining various coating concentrations of dyes and sand weights,we discovered that sand loaded with Rhodamine B(RhB)exhibits high activity for the photo-oxidation of NO.A combination results of X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),Fourier transform infrared spectroscopy(FTIR)and thermogravimetric(TG)analyses confirm the presence of SiO_(2),cacO_(3),Al_(2)O_(3)and iron oxides as the main components of the ***,studying RhB-loaded individual components reveals that cacO_(3)plays a crucial role in enhancing the NO removal *** results and theoretical calculations demonstrate the establishment of a directional charge transfer channel from cacO_(3)to RhB,facilitating the adsorption and activation of molecular NO and O_(2).This work not only promotes the utilization of natural mineral resources but also enriches the fields of environmental photochemistry and semiconductor photocatalysis.

关键词： Sand dyes Rhodamine B Photo-oxidation of NO Visible light illumination

Rescattering of stimulated Raman side scattering in nonuniform plasmas

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Matter and Radiation at Extremes 2024年第5期9卷 68-76页

作者： S.tan Q.Wang Y.chen W.B.Yao c.Z.Xiao J.F.Myatt School of Physics and Electronics Hunan UniversityChangsha 410082China Institute of Applied Physics and computational Mathematics Beijing 100094China School of Electrical and Information Engineering Anhui University of Science and TechnologyHuainanAnhui 232001China Department of Electrical and computer Engineering University of Alberta9211116 St.NWEdmontonAlberta T6G 1H9Canada

Rescattering of stimulated Raman side scattering(SRSS)is observed for the first time via two-dimensional(2D)particle-in-cell(PIc)*** construct a theoretical model for the rescattering process,which can predict the region of occurrence of mth-order SRSS and estimate its *** rescattering process is identified by the 2D PIc simulations under typical conditions of a direct-drive inertial confinement fusion *** electrons produced by second-order SRSS propagate nearly perpendicular to the density gradient and gain nearly the same energy as in first-order SRSS,but there is no cascade acceleration to produce superhot *** studies for a wide range of ignition conditions show that SRSS and associated rescatterings are robust and important processes in inertial confinement fusion.

关键词： nonuniform acceleration scattering

Mechanical behavior and damage constitutive model of sandstone under hydro-mechanical (H-M) coupling

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International Journal of Mining Science and Technology 2024年第6期34卷 837-853页

作者： Tao tan chunyang Zhang Yanlin Zhao Xiaoshuang Li School of Resources and Environmental Engineering Wuhan University of TechnologyWuhan 430070China State Key Laboratory of Safety and Health in Metal Mines Maanshan 243000China Sinosteel Maanshan General Institute of Mining Research co. Ltd.Maanshan 243000China School of Resource&Environment and Safety Engineering Hunan University of Science and TechnologyXiangtan 411201China School of Urban construction Changzhou UniversityChangzhouJiangsu 213164China

Underground engineering often passes through water-rich fractured rock masses, which are prone to fracture and instability under the long-term coupling of in-situ stress field and pore water(P-W) pressure, ultimately threatening the stability of underground structures. In order to explore the mechanical properties of rocks under H-M coupling, the corresponding damage constitutive(D-c) model has become the focus of attention. considering the inadequacy of the current research on rock strength parameters,energy evolution characteristics and D-c model under H-M coupling, the mechanical properties of typical sandstone samples are discussed based on laboratory tests. The results show that the variation of characteristic stresses of sandstone under H-M coupling conforms to the normalized attenuation equation and Mohr-coulomb(M-c) criterion. The P-W pressure mechanism of sandstone exhibits a dynamic change from softening effect to H-M fracturing effect. The closure stress is mainly provided by cohesive strength, while the initiation stress, damage stress, and peak stress are jointly dominated by cohesive strength and friction strength. In addition, residual stress is attributed to the friction strength formed by the bite of the fracture surface. Subsequently, the energy evolution characteristics of sandstone under H-M coupling were studied, and it was found that P-W pressure weakened the energy storage capacity and energy dissipation capacity of sandstone, and H-M fracturing was an important factor in reducing its energy storage efficiency. Finally, combined with energy dissipation theory and statistical damage theory, two types of D-c models considering P-W pressure are proposed accordingly, and the model parameters can be determined by four methods. The application results indicate that the proposed and modified D-c models have high reliability, and can characterize the mechanical behavior of sandstone under H-M coupling, overcome the inconvenience of existing D-c models

关键词： H-M coupling Water-saturated sandstone Mechanical mechanism Energy evolution D-c model

Light quarkonium and charmonium mass shifts in an unquenched quark model

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chinese Physics c 2024年第9期48卷 96-106页

作者： Xiaoyun chen Yue tan college of Science Jinling Institute of TechnologyNanjing 211169China Department of Physics Yancheng Institute of TechnologyYancheng 224000China

The unquenched quark model for the light quarkonium and charmonium states is explored in this *** quark-pair creation operator in the^(3)P_(0) model,which combines the two-quark and four-quark components,is modified by considering the effects of the created quark pair's ***,the separation between the created quark pair and valence quark pair is *** the wave functions,including those for the mesons and the relative motion between two mesons,are obtained by solving the corresponding Schrodinger equation using the Gaussian expansion *** aim of this study is to find a new set of parameters that can accurately describe the mass spectrum of low-lying light quarkonium and charmonium ***,certain exotic states,such as X(3872),can be described well in the unquenched quark model.

关键词： the unquenched quark model Gaussian expansion method light quarkonium and charmonium states

Elevated brain temperature under severe heat exposure impairs cortical motor activity and executive function

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Journal of Sport and Health Science 2024年第2期13卷 233-244页

作者： Xiang Ren tan Mary c.Stephenson Sharifah Badriyah Alhadad Kelvin W.Z.Loh Tuck Wah Soong Jason K.W.Lee Ivan c.c.Low Health and Social Sciences Singapore Institute of TechnologySingapore 138683Singapore Human Potential Translational Research Programme Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117597Singapore centre for Translational Magnetic Resonance Research Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117549Singapore Department of Physiology Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117593Singapore Heat Resilience and Performance centre Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117510Singapore N.1 Institute for Health National University of SingaporeSingapore 117456Singapore campus for Research Excellence and Technological Enterprise(cREATE) Singapore 138602Singapore

Background:Excessive heat exposure can lead to hyperthermia in humans,which impairs physical performance and disrupts cognitive *** heat is a known physiological stressor,it is unclear how severe heat stress affects brain physiology and ***:Eleven healthy participants were subjected to heat stress from prolonged exercise or warm water immersion until their rectal temperatures(T_(re))attained 39.5℃,inducing exertional or passive hyperthermia,*** a separate trial,blended ice was ingested before and during exercise as a cooling *** were compared to a control condition with seated rest(normothermic).Brain temperature(T_(br)),cerebral perfusion,and task-based brain activity were assessed using magnetic resonance imaging ***:T_(br)in motor cortex was found to be tightly regulated at rest(37.3℃±0.4℃(mean±SD))despite fluctuations in T_(re).With the development of hyperthermia,T_(br)increases and dovetails with the rising T_(re).Bilateral motor cortical activity was suppressed during high-intensity plantarflexion tasks,implying a reduced central motor drive in hyperthermic participants(T_(re)=38.5℃±0.1℃).Global gray matter perfusion and regional perfusion in sensorimotor cortex were reduced with passive *** function was poorer under a passive hyperthermic state,and this could relate to compromised visual processing as indicated by the reduced activation of left lateral-occipital ***,ingestion of blended ice before and during exercise alleviated the rise in both T_(re)and T_(bc)and mitigated heat-related neural ***:Severe heat exposure elevates T_(br),disrupts motor cortical activity and executive function,and this can lead to impairment of physical and cognitive performance.

关键词： Brain functional activity cognition Heat stress Hyperthermia Motor function

Research of surface-enhanced Raman scattering on Ag@PMBA@c@Au hybrid nanoparticles

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Optoelectronics Letters 2024年第2期20卷 65-69页

作者： tan Enzhong LÜ Suye Liberal Study college Beijing Institute of Petrochemical TechnologyBeijing 102617China

Monodispersed, biocompatible, and readily-functionalized hybrid reporter-embedded core-shell nanopartilces(NPs) have been prepared in a simple route. This composite offers a potential platform for immunochemical detection using surface-enhanced Raman scattering(SERS) due to their high sensitivity, good stability and biocompatiblity. This also provides a new platform for insight into SERS enhancement mechanism.

关键词： mechanism. readily SERS

Rubik's cube as in-situ programmable matter and a reconfigurable mechanical metamaterial

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Science china Technological Sciences 2024年第10期67卷 3221-3234页

作者： ZHU ShaoWei cHEN Huan YANG XiaoQiang tan Li JIN Shuai cHEN LiMing LIU Tao tan XiaoJun WANG Lianchao WANG Bing MUAMER Kadic college of Aerospace Engineering Chongqing University State Key Laboratory of coal Mine Disaster Dynamics and control Chongqing University School of civil Aviation Northwestern Polytechnical University National Key Laboratory of Science and Technology on Advanced composites in Special Environments Harbin Institute of Technology Institut FEMTO-ST CNRS UMR 6174University Bourgogne

As part of the 4th industrial revolution, programmable mechanical metamaterials exhibit great application potential in flexible robotics, vibration control, and impact protection. However, maintaining a programmed state without sustaining the external stimulus is often challenging and leads to additional energy consumption. Inspired by Rubik's cube, we design and study an insitu programmable and distribution-reconfigurable mechanical metamaterial(IPDR-MM). A matrix model is developed to model IPDR-MMs and describe their morphological transitions. Based on this model, the reinforcement learning method is employed to find the pathways for morphological transitions. We find that IPDR-MMs have controllable stiffness across several orders of magnitude and a wide range of adjustable anisotropies through morphology transformation. Additionally, because of the independence of the directions of morphology transformation and bearing, IPDR-MMs exhibit good stability in bearing and can readily achieve high stiffness. The Rubik's cube-inspired design concept is also instructive for other deformable structures and metamaterials, and the current version of the proposal should be sufficiently illustrative to attract and broaden interdisciplinary interests.

关键词： mechanical metamaterials in-situprogrammable distribution-reconfigurable Rubik's cube controllable stiffness and anisotropy