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Nano Research 2024年第9期17卷 8627-8637页

作者： Shan-Fei wang Yangyang Li Haiyan wang Jin-Xia Liang chun Zhu Botao Qiao School of Chemistry and Chemical Engineering Guizhou UniversityGuiyang 550025China CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China University of Chinese Academy of Sciences Beijing 100049China

Oxide-supported metal single-atom catalysts(SACs)have exhibited excellent catalytic performance for water-gas shift(WGS)***,we report the single-atom catalyst Pt1/FeOx exhibits excellent medium temperature catalytic performance for WGS reactions by the density functional theory(DFT)calculations and experimental *** calculations indicate that H_(2)O molecules are easily dissociated at oxygen vacancies,and the formed*OH and*O are adsorbed on Pt1 single atoms and the adjacent O atoms,*** studying four possible reaction mechanisms,it is found that the optimal WGS reaction pathway is proceeded along the carboxyl mechanism(pathway III),in which the formation of*COOH intermediates can promote the stability of Pt1/FeOx SAC and the easier occurrence of WGS *** energy barrier of the rate-determining step during the entire reaction cycle is only 1.16 eV,showing the high activity for the medium temperature WGS reaction on Pt1/FeOx SAC,which was verified by experimental ***,the calculated turnover frequencies(TOFs)of CO_(2)and H_(2)formation on Pt1/FeOx at 610 K(337℃)can reach up to 1.14×10^(-3)s^(-1)·site^(-1)through carboxyl *** this work,we further expand the application potential of Pt1/FeOx SAC in WGS reaction.

关键词： water-gas shift(WGS)reaction single-atom catalyst(SAC) density functional theory(DFT) thermocatalysis

Feature matching using quasi-conformal maps

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Frontiers of Information Technology & Electronic Engineering 2017年第5期18卷 644-657页

作者： chun-xue wang Li-gang LIU School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026China

We present a fully automatic method for finding geometrically consistent correspondences while discarding outliers from the candidate point matches in two images. Given a set of candidate matches provided by scale-invariant feature transform(SIFT) descriptors, which may contain many outliers, our goal is to select a subset of these matches retaining much more geometric information constructed by a mapping searched in the space of all diffeomorphisms. This problem can be formulated as a constrained optimization involving both the Beltrami coefficient(BC) term and quasi-conformal map, and solved by an efficient iterative algorithm based on the variable splitting method. In each iteration, we solve two subproblems, namely a linear system and linearly constrained convex quadratic programming. Our algorithm is simple and robust to outliers. We show that our algorithm enables producing more correct correspondences experimentally compared with state-of-the-art approaches.

关键词： Feature correspondence Quasi-conformal map Splitting method

Trends in Fruit and Vegetable Intake Among the Labor Force Population—China,2010-2018

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China CDC weekly 2024年第18期6卷 401-407,I0008页

作者： Lan wang Mei Zhang Xiao Zhang Zhenping Zhao chun Li Mengting Yu Taotao xue Feng Tan Limin wang Division of Chronic Disease and Risk Factor Surveillance National Center for Chronic and Non-communicable Disease Control and PreventionChinese Center for Disease Control and PreventionBeijingChina Chinese Center for Disease Control and Prevention BeijingChina

Introduction:This research investigates trends pertaining to the prevalence of low fruit and vegetable consumption among the labor force population in *** study considered data derived from four nationally representative cross-sectional ***:The data under review for this study was derived from the China Chronic Disease and Risk Factor Surveillance(CCDRFS)carried out in 2010,2013,2015,and 2018,*** utilized a food frequency questionnaire to evaluate the quantity and frequency of fruit and vegetable *** estimated prevalence of low fruit and vegetable consumption was calculated for each survey,while considering factors such as sex,age,location,and socioeconomic status(SES).Participants’SES was ascertained via latent class analysis,serving to identify distinct classes based on criteria such as education,occupation,and household income per *** regression was deployed to determine the statistical significance of ***:From 2010 to 2018,there was a notable increase in the average daily consumption of vegetables and fruits among the working population,rising from 418.6 g/day to 491.8 g/day(P0.05 for trend).Conclusion:Over the past nine years,there has been a notable decline in the prevalence of low fruit and vegetable consumption among the labor force population in ***,the comparatively deficient intake of fruits and vegetables evident among individuals of lower SES warrants further attention.

关键词： intake occupation utilized

Energy transfer, anticounterfeiting, white light emission and sensing in fine-regulating series of lanthanide metal-organic frameworks

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Journal of Rare Earths 2024年第3期42卷 446-454,I0001页

作者： Juanjuan xue Yao wang Guoping Yang Yaoyu wang Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education Shaanxi Key Laboratory of Physico-Inorganic ChemistryCollege of Chemistry&Materials ScienceNorthwest UniversityXi'an710127China

Three lanthanide ions and a rigid(1,1'-biphenyl)-2,4,6-tricarboxylic acid(H_(3)bptc) ligand led to the isostructural lanthanide metal-organic frameworks(Ln-MOFs) {[Ln(bptc)(H_(2)O)_(3)]·3H_(2)O}_n(Lnbptc, Ln = Eu,Tb, Gd, Eu_(x)Tb_(1—x), Eu_(x)Gd_(1-x), Tb_(x)Gd_(1-x), and Eu_(0.12)Tb_(0.52)Gd_(0.36)). The density functional theory(DFT) and time-dependent DFT calculation were expanded on H_3bptc, which point to the occurrence of “antenna effect”. The minor diameter samples of Eubptc, Tbbptc, and Gdbptc can also be attained via the microwave synthesis and employed for handwriting anticounterfeiting. Interestingly, the typical red emission of Eu^(3+) and green emission of Tb~(3+) could be fine-tuned by Gd^(3+) via chemical mixing to be full-color emissions bimetallic doped Eu_(x)Tb_(1-x)bptc, Eu_(x)Gd_(1-x)bptc, and Tb_(x)Gd_(1-x)bptc. The above synthetic bimetallic MOFs can be fixed in positioning boxes of quick response(QR) codes with diverse emission for anticounterfeiting. The message can be decoded under the irradiation of 365 nm ultraviolet lamp while invisible in the daylight. Notably, the trimetallic doped Eu_(0.12)Tb_(0.52)Gd_(0.36)bptc emits white light with the CIE color coordinate(0.34, 0.34). Furthermore, Tbbptc is demonstrated to be a sensitive probe toward nitrobenzene and acetone with multiple mechanisms.

关键词： Metal-organic frameworks Anticounterfeiting White light-emitting Sensing Rare earths

Pb induced dislocation defects of PtCo systems: Strain-triggered oxygen reduction reaction for PEMFC

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Nano Research 2024年第4期17卷 2462-2472页

作者： chun Jin Qiheng wang Jingjun Liu Beijing Key Laboratory of Electrochemical Process and Technology for Materials Beijing 100029China Beijing University of Chemical Technology Beijing 100029China

Design and development of advanced electrocatalysts with high performance and low Pt consumption are crucial for reducing the kinetic energy barrier of the cathode oxygen reduction reaction(ORR)and improving the efficiency of proton exchange membrane fuel cells(PEMFC).In this study,we demonstrate a Pb-modulated PtCo system for efficient ORR,in which the inclusion of Pb in ternary alloys induces dislocation defects due to the significant difference in atomic ***-PtCoPb was confirmed to exhibit significantly higher ORR activity and stability in acidic *** practical PEMFC applications,it outperforms the corresponding commercial Pt/C with a mass activity of 0.58 A·mgPt^(-1),making it a promising alternative to state-of-the-art Pt-based *** combination of experimental results and density functional theory(DFT)calculations offers valuable atomic-level insights into the dislocation *** with a larger atomic radius is located in the lattice stretching region below the dislocation slip plane,forming a structure similar to a Cottrell atmosphere,which reduces the dislocation energy and puts the system in a lower energy *** Cottrell atmosphere pins the dislocation structure and stabilizes the ternary *** adjusting the amount of added Pb,a moderate level of dislocation density induces a tuned strain effect,thereby enhancing the electrocatalytic mechanism by optimizing the electronic structure of the alloy surface and the adsorption and desorption of oxygen *** work provides valuable insights into the design and development of lattice dislocation defect structures to trigger strain effects for improving ORR performance.

关键词： dislocation defect strain effect Pb-modulated oxygen reduction reaction

Ore Geology,H-O-C Isotopes and 40Ar-39Ar Dating of the Wutonggou Iron Deposit,Eastern Tianshan,NW China:Implications for the Source,Timing,and Genesis of Hydrothermal Mineralization in a Sedimentary Iron Deposit

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Journal of Earth Science 2024年第4期35卷 1170-1185页

作者： chun-Long wang Yi-Tian wang State Key Laboratory of Geological Processes and Mineral Resources Collaborative Innovation Center for Exploration of Strategic Mineral ResourcesSchool of Earth ResourcesChina University of GeosciencesWuhan430074China MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing100037China

The Wutonggou iron deposit is located in the well-known iron metallogenic belt in the eastern Tianshan,NW China,and has been regarded as a sedimentary iron *** hydrothermal overprinting could play indispensable roles in the formation of high-grade iron ores in sedimentary iron deposits,previous studies mainly focused on sedimentary-related iron mineralization,while the nature and contribution of hydrothermal fluids are poorly ***,an integrated study of ore geology,H-O-C isotopes and^(40)Ar-^(39)Ar dating,is conducted on the Wutonggou deposit,in order to reveal the features,source,and timing of hydrothermal *** studied deposit includes two mining sections namely the Jianshan and ***δ^(18)O values of early magnetite from the Jianshan section range from+3.0‰to+5.8‰that nearly consistent with classic magmatic magnetite,while increase to 6.3‰-8.0‰in the late *** from the two sections shows comparable H-O isotopic compositions and identical fractionation trends,and is plotted in or periphery to the primary magmatic water *** from the two sections are broadly similar in carbon and oxygen isotopic compositions,and siderite from the Wutonggou section is plotted in the same ***,comparable stable isotopic compositions and evolution trends indicate similar magmatic fluids contributed hydrothermal iron mineralization in the two mining ***,water-rock interactions of varying degrees generated distinct mineralization styles in the Jianshan and Wutonggou sections,and caused the isotopic fractionation in late *** extracted from a hydrothermal siderite ore yielded a^(40)Ar-^(39)Ar plateau age of 299.5±2.0 Ma,indicates the timing of hydrothermal iron mineralization is corresponding to the emplacement of vicinity *** together,the hydrothermal mineralization in the Wutonggou iron deposit was the product of remobilization and upgrading of early sedimentary iron ores,a

关键词： iron deposits H-O-C isotopes 40Ar-39Ar dating sedimentary iron deposits Wutonggou iron deposit eastern Tianshan

The Boundary Element Method for Ordinary State-Based Peridynamics

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2807-2834页

作者： xue Liang Linjuan wang State Key Laboratory for Turbulence and Complex Systems Department of Mechanics and Engineering ScienceCollege of EngineeringPeking UniversityBeijing100871China CAPT-HEDPS and IFSA Collaborative Innovation Center of MoECollege of EngineeringPeking UniversityBeijing100871China School of Astronautics Beihang UniversityBeijing100191China

The peridynamics(PD),as a promising nonlocal continuum mechanics theory,shines in solving discontinuous *** to now,various numerical methods,such as the peridynamic mesh-free particlemethod(PD-MPM),peridynamic finite element method(PD-FEM),and peridynamic boundary element method(PD-BEM),have been ***-BEM,in particular,outperforms other methods by eliminating spurious boundary softening,efficiently handling infinite problems,and ensuring high computational ***,the existing PD-BEM is constructed exclusively for bond-based peridynamics(BBPD)with fixed Poisson’s ratio,limiting its applicability to crack propagation problems and scenarios involving infinite or semi-infinite *** this paper,we address these limitations by introducing the boundary element method(BEM)for ordinary state-based peridynamics(OSPD-BEM).Additionally,we present a crack propagationmodel embeddedwithin the framework ofOSPD-BEM to simulate crack *** validate the effectiveness of OSPD-BEM,we conduct four numerical examples:deformation under uniaxial loading,crack initiation in a double-notched specimen,wedge-splitting test,and threepoint bending *** results demonstrate the accuracy and efficiency of OSPD-BEM,highlighting its capability to successfully eliminate spurious boundary softening phenomena under varying Poisson’s ***,OSPDBEMsignificantly reduces computational time and exhibits greater consistencywith experimental results compared to PD-MPM.

关键词： Ordinary state-based peridynamics boundary element method crack propagation fracture toughness

Photocatalytic degradation of methylene blue over MIL-100(Fe)/GO composites: a performance and kinetic study

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International Journal of Coal Science & Technology 2024年第3期11卷 208-222页

作者： Yuxue Wei Zhiyuan Fu Yingzi Meng chun Li Fu Yin xue wang Chenghua Zhang Lisheng Guo Song Sun School of Chemistry and Chemical Engineering Anhui UniversityHefei230601AnhuiChina Anhui Tanxin Technology Co. LtdHuaibei235141AnhuiChina

Adsorption coupled with photocatalytic degradation is proposed to fulfill the removal and thorough elimination of organic ***,we report a facile hydrothermal synthesis of MIL-100(Fe)/GO *** adsorption and photocatalytic degradation process of methylene blue(MB)on MIL‐100(Fe)/GO composites were systematically studied from performance and kinetic perspectives.A possible adsorption‐photocatalytic degradation mechanism is *** optimized 1M8G composite achieves 95%MB removal(60.8 mg/g)in 210 min and displays well recyclability over ten *** obtained MB adsorption and degradation results are well fitted onto Langmuir isotherm and pseudo‐second order kinetic *** study shed light on the design of MOFs based composites for water treatment.

关键词： Graphene oxide Metal organic frameworks Methylene blue Adsorption Photocatalytic degradation

A study on the impact of heritage protection on urban carbon emissions

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Science China(Technological Sciences) 2024年第9期67卷 2675-2692页

作者： wang Fang xue PengCheng wang ShunYi LIU YunHuai River Basin Habitats Research Center College of Architecture and Landscape ArchitecturePeking UniversityBeijing 100871China Shanxi Key Laboratory of Watershed Built Environment with Locality(Peking University) Peking UniversityBeijing 100871China College of Urban and Environmental Sciences Peking UniversityBeijing 100871China School of Computer Science Peking UniversityBeijing 100871China

A major goal of current international urban development and construction is to lower carbon *** exist between the preservation of historic cities and the development of low-carbon cities;however,the relationship between preservation of historic cities and carbon emissions remains *** study focuses on the cities in the“Yellow-Canal-Yangtze”watershed community,which includes the Yellow River Basin,Yangtze River Basin,and the Grand Canal region,and aims to verify the differences in CO_(2) emissions(CE)between historic and non-historic cities through multiple comparisons after ***,Ridge Regression was used to determine the impact and dimensions of the relevant variables associated with the preservation of historic cities on *** with national development goals,this study predicts changes in the CE of historic city preservation under different *** study found significant differences between historic and non-historic cities,as the total CE of historic cities is 2.42 times higher than that of non-historic *** dimension with the largest difference was the CE related to transportation,with aviation emissions of historic cities reaching 15.22 times higher than that of non-historic *** the preservation of historic cities has led to an overall increase in the CE,there is significant potential for CE reduction in land use,transportation infrastructure,and tourism development related to historic city *** the future,historic cities can contribute to China's carbon neutrality and the United Nation's development goals through the creation of larger historical preservation areas,more convenient public transportation,and more vibrant tourism.

关键词： CO_(2) emissions urban planning cultural heritage historic city “Yellow-Canal-Yangtze”watershed community

Some Convergence Properties for Weighted Sums of Martingale Difference Random Vectors

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Acta Mathematica Sinica,English Series 2024年第4期40卷 1127-1142页

作者： Yi WU xue Jun wang School of Big Data and Artificial Intelligence Chizhou UniversityChizhou 247000P.R.China School of Big Data and Statistics Anhui UniversityHefei 230601P.R.China

Let{X_(ni),F_(ni);1≤i≤n,n≥1}be an array of R^(d)martingale difference random vectors and{A_(ni),1≤i≤n,n≥1}be an array of m×d matrices of real *** this paper,the Marcinkiewicz-Zygmund type weak law of large numb... 详细信息

关键词： Martingale difference random vectors weighted sums Marcinkiewicz–Zygmund type weak law of large numbers complete convergence strong law of large numbers multivariate simple linear regression model