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Dynamic manipulation of multimodal emission in Er^(3+)-activated non-core-shell structure for optical thermometry and information security

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Rare Metals 2024年第4期43卷 1702-1712页

作者： Xuan Liu Zi-xia Lin Yin-Biao Shi xiao-Yan Wang Ming-ye Ding xiao-Fei Yang College of Science Nanjing Forestry UniversityNanjing210037China Testing Center Yangzhou UniversityYangzhou225009China

Regulating luminescent dynamics of lanthanide-based luminescent materials via external stimuli is of great significance in the fields of optical thermometry and high-level ***,it is still a huge challenge to realize multimodal emissions with tunable color outputs from a single activator in simple structures via smart dynamic control of photon transition ***,we present a mechanistic strategy to achieve multimodal luminescence of Er^(3+)activators with color-switchable outputs in a non-core-shell *** the control of excitation dynamics(λ_(ex)=980,808,1532,377 nm),the population among the intermediate en ergy levels of Er^(3+)and the interaction between Er^(3+)and Yb^(3+)could be precisely modulated through energy transfer and migration processes,leading to the generation of colortunable multimodal luminescence upon diverse excitation modes(non-steady-state,single-/dual-wavelength steady,thermal activation).Inspired by its special luminescent performance,the as-obtained material exhibits great potential in noncontact thermometry,multimodal anticounterfeiting,and high-capacity information encryption by performing a series of proof-of-concept *** findings might provide a conceptual model to modulate the luminescent dynamics in a simple-structured system for the generation of color-adjustable multimodal emissions,which is convenient for the development of advanced luminescent materials toward versatile cuttingedge applications.

关键词： Lanthanide ions Multimodal emission Upconversion Downshifting Anti-counterfeiting Luminescent thermometry

Buckling optimization of curvilinear fiber-reinforced composite structures using a parametric level set method

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Frontiers of Mechanical Engineering 2024年第1期19卷 149-160页

作者： ye TIAN Tielin SHI Qi xia State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China

Owing to their excellent performance and large design space,curvilinear fiber-reinforced composite structures have gained considerable attention in engineering fields such as aerospace and *** addition to the stiffness and strength of such structures,their stability also needs to be taken into account in the *** study proposes a level-set-based optimization framework for maximizing the buckling load of curvilinear fiber-reinforced composite *** the proposed method,the contours of the level set function are used to represent fiber *** a composite laminate with a certain number of layers,one level set function is defined by radial basis functions and expansion coefficients for each ***,the fiber angle at an arbitrary point is the tangent orientation of the contour through this *** the finite element of buckling,the stiffness and geometry matrices of an element are related to the fiber angle at the element *** study considers the parallelism constraint for fiber *** the sensitivity calculation of the objective and constraint functions,the method of moving asymptotes is utilized to iteratively update all the expansion coefficients regarded as design *** numerical examples under different boundary conditions are given to validate the proposed *** show that the optimized curved fiber paths tend to be parallel and equidistant regardless of whether the composite laminates contain holes or ***,the buckling resistance of the final design is significantly improved.

关键词： buckling optimization curvilinear fiber composite structure level set method manufacturing constraint

Numerical simulations for radon migration and exhalation behavior during measuring radon exhalation rate with closed-loop method

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Nuclear Science and Techniques 2024年第1期35卷 81-95页

作者： Ming xia Yong-Jun ye Shu-Yuan Liu School of Resources Environment and Safety Engineering University of South ChinaHengyang 421001China Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy University of South ChinaHengyang 421001China

Accurate measurements of the radon exhalation rate help identify and evaluate radon risk regions in the *** these measurement methods,the closed-loop method is frequently ***,traditional experiments are insufficient or cannot analyze the radon migration and exhalation patterns at the gas–solid interface in the accumulation *** CFD-based technique was applied to predict the radon concentration distribution in a limited space,allowing radon accumulation and exhalation inside the chamber intuitively and *** this study,three radon exhalation rates were defined,and two structural ventilation tubes were designed for the *** consistency of the simulated results with the variation in the radon exhalation rate in a previous experiment or analytical solution was *** effects of the vent tube structure and flow rate on the radon uniformity in the chamber;permeability,insertion depth,and flow rate on the radon exhalation rate and the effective diffusion coefficient on back-diffusion were *** on the results,increasing the inser-tion depth from 1 to 5 cm decreased the effective decay constant by 19.55%,whereas the curve-fitted radon exhalation rate decreased(lower than the initial value)as the deviation from the initial value increased by approximately 7%.Increasing the effective diffusion coefficient from 2.77×10^(-7) to 7.77×10^(-6) m^(2) s^(-1) made the deviation expand from 2.14 to 15.96%.The conclusion is that an increased insertion depth helps reduce leakage in the chamber,subject to notable back-diffusion,and that the closed-loop method is reasonably used for porous media with a low effective diffusion coefficient in view of the back-diffusion *** CFD-based simulation is expected to provide guidance for the optimization of the radon exhalation rate measurement method and,thus,the accurate measurement of the radon exhalation rate.

关键词： Radon exhalation Numerical simulation Accumulation chamber

Eigenfrequency analysis of bridges using a smartphone and a novel low-cost accelerometer prototype

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Frontiers of Structural and Civil Engineering 2024年第2期18卷 202-215页

作者： Seyedmilad KOMARIZADEHASL ye xia Mahyad KOMARY Fidel LOZANO Department of Civil and Environment Engineering Universitat Politècnica de CatalunyaBarcelona 08034Spain Department of Bridge Engineering Tongji UniversityShanghai 200092China Department of Civil Engineering Universidad de Castilla-La ManchaCiudad Real 13071Spain

Researchers are paying increasing attention to the development of low-cost and microcontroller-based accelerometers,in order to make structural health monitoring feasible for conventional bridges with limited monitoring *** with the low-cost sensor development,the use of the embedded accelerometers of smartphones for eigenfrequency analysis of bridges is becoming popular in the civil engineering *** paper,for the first time in the literature,studies these two promising technologies by comparing the noise density and eigenfrequency analysis of a self-developed,validated and calibrated low-cost Internet of things based accelerometer LARA(low cost adaptable reliable accelerometer)with those of a state of the art smartphone(iPhone XR).The eigenfrequency analysis of a footbridge in San Sebastian,Spain,showed that the embedded accelerometer of the iPhone XR can measure the natural frequencies of the under study bridge.

关键词： smartphone modal analysis eigenfrequency analysis low-cost accelerometers Arduino Raspberry Internet of things

Deadline-Constrained and Cost-Effective Multi-Workflow Scheduling with Uncertainty in Cloud Control Systems

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Journal of Systems Science & Complexity 2024年第5期37卷 1861-1886页

作者： ye Lingjuan YANG Liwen xia Yuanqing ZHAN Yufeng ZHAO Xinchao School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China Key Laboratory of Mathematics and Information Networks Beijing University of Posts and TelecommunicationsMinistry of EducationBeijing 100876China School of Automation Nanjing University of Information Science and TechnologyNanjing 210044China School of Automation Beijing Institute of TechnologyBeijing 100081China

In cloud control systems,generating an efficient and economical workflow scheduling strategy for deadline-constrained workflow applications,especially in uncertain multi-workflow dynamic scheduling processes,is a crucial *** optimize the total cost of workflow scheduling,the authors propose a cost-driven heuristic scheduling algorithm F-MWSA which consists of two phases:Fuzzy deadline distribution and fuzzy task *** the fuzzy deadline distribution phase,a new workflow deadline distribution strategy with fuzziness is designed to obtain the sub-deadline constraint of each *** fuzzy task scheduling phase focuses on a cost-effective strategy to assign tasks to cloud resources,reducing multi-workflow scheduling *** evaluations on five real-world workflows demonstrate that the proposed F-MWSA outperforms the baseline policy in terms of total cost,success ratio,resource utilization,and makespan.

关键词： Cloud computing cost-effective deadline constraint multi-workflow scheduling uncertainty

Harmonic Transfer Function Based Single-input Single-output Impedance Modeling of LCC-HVDC Systems

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1327-1332页

作者： Yang Wang Fei xia Ying Wang xianyong xiao College of Electrical Engineering Sichuan UniversityChengdu 610065China

This study presents a harmonic transfer function(HTF)based single-input single-output(SISO)impedance modeling *** method converts an HTF from phase domain to sequence domain and then transforms it into an SISO impedance while preserving the frequency coupling information of different sequences and different *** of this method to a line-commutated converter based high-voltage direct current(LCC-HVDC)system are *** results demonstrate the accuracy of the derived SISO impedance,and a truncation-order selection is *** case study shows that the proposed method facilitates simpler impedance measurements and associated stability analysis.

关键词： Line-commutated converter based high-voltage direct current(LCC-HVDC) harmonic transfer function(HTF) single-input single-output(SISO)impedance frequency coupling

Occurrence of dark septate endophytes in Phragmites australis in the Baiyang Lake and their resistance to Cd stress

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Pedosphere 2024年第2期34卷 484-496页

作者： Minghui XU xia LI Qiannan ye Feng GONG Xueli HE School of Life Sciences Hebei UniversityBaoding 071002China Key Laboratory of Microbial Diversity Research and Application of Hebei Province Hebei UniversityBaoding 071002China

Heavy metal pollution poses a serious hazard to human health,and microbial remediation of heavy metals in soil has been widely studied.A group of ascomycetes classified as dark septate endophytes(DSEs)colonize plant roots and benefit host plants under abiotic stress *** this study,Phragmites australis,a common remediation plant in the Baiyang Lake in North China,was *** and roots of *** were collected in typical heavy metal-contaminated sites,and the species diversity and community structure of DSEs in *** roots were *** addition,DSE strains were isolated,cultured,and tested for their tolerance to Cd *** results showed that DSEs occurred extensively in *** roots,forming typical dark septate hyphae,with a total colonization rate of 19.7%–83.1%.Morphological and internal transcribed spacer sequencing analyses were used to identify 10 species within 9 genera of DSE *** these fungi,6 strains with considerable resistance to Cd stress were *** biomasses of Poaceascoma helicoides,Alternaria doliconidium,and Acrocalymma vagum strains increased as the Cd levels *** results can not only help to understand plant-DSE interactions in wetland environments,but also provide a theoretical basis for making full use of DSE fungi to alleviate heavy metal contamination in soil.

关键词： ascomycete colonization rate contaminated site evenness index heavy metal Shannon-Wiener index Simpson index wetland

Insight into the Role and Evidence of Oxygen Vacancies in Porous Single-Crystalline Oxide to Enhance Catalytic Activity and Durability

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Research 2024年第2期2023卷 675-683页

作者： Lingting ye Jiaming Ma Jie Zhang Wen Yin Yuanguang xia Kui Xie Key Laboratory of Optoelectronic Materials Chemistry and Physics Fujan Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhouFujian 350002China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China FuzhouFujian 350108China Advanced Energy Science and Technology Guangdong Laboratory 29 Sanxin North RoadHuizhouGuangdong 116023China Spallation Neutron Source Science Center DongguanGuangdong 523803China

Introducing and stabilizing oxygen vacancies in oxide catalysts is considered to be a promising strategy for improving catalytic activity and ***,we quantitatively create oxygen vacancies in the lattice of porous single-crystallineβ-Ga_(2)O_(3)monoliths by reduction treatments and stabilize them through the long-range ordering of crystal lattice to enhance catalytic activity and *** combination analysis of time-of-flight neutron powder diffraction and extended x-ray absorption fine structure discloses that the preferential generation of oxygen vacancy tends to occur at the site of tetrahedral coordination oxygen ions(O_(Ⅲ)sites),which contributes to the formation of unsaturated Ga-O coordination in the monoclinic *** oxygen vacancies are randomly distributed in lattice even though some of them are present in the form of domain defect in the PSC Ga_(2)O_(3)monoliths after the reduction *** number of oxygen vacancies in the reduced monoliths gives 2.32×10^(13),2.87×10^(13),and 3.45×10^(13)mg^(-1)for the Ga_(2)O_(2.952),Ga_(2)O_(2.895),and Ga_(2)O_(2.880),*** therefore demonstrate the exceptionally high C_(2)H_(4)selectivity of~100%at the C_(2)H_(6)conversion of~37%for nonoxidative dehydrogenation of C_(2)H_(6)to C_(2)H_(4).We further demonstrate the excellent durability even at 620℃for 240 h of continuous operation.

关键词： durability coordination Oxygen

Unraveling the stereoscopic gene transcriptional landscape of zebrafish using Fish SED,a fish spatial expression database with multispecies scalability

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Science China(Life Sciences) 2024年第4期67卷 843-846页

作者： Cheng Guo Weidong ye Danying Cao Mijuan Shi Wanting Zhang Yingyin Cheng Yaping Wang xiao-Qin xia Institute of Hydrobiology Chinese Academy of SciencesWuhan 430072China College of Advanced Agricultural Sciences University of Chinese Academy of SciencesBeijingChina The Innovative Academy of Seed Design Chinese Academy of SciencesBeijing 100101China

Dear Editor,The expression profile demonstrates how each gene was expressed in the target tissue or cell at a given *** heterogeneity is a biological concept characterized by the presence of numerous cells with varying functions and expression profiles within organ/tissue *** is also cell-to-cell signaling,which implies that the extracellular environment and spatial location influence intracellular transcription,resulting in spatial heterogeneity of gene expression within the same cell type.

关键词： landscape fish database