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International Journal of Minerals,Metallurgy and Materials 2024年第4期31卷 803-811页

作者： Xiaoyan Wang Safeer Jan Zhiyong Wang Xianbo jin College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power SourcesWuhan UniversityWuhan 430072China Engineering Research Center of Organosilicon Compounds&Materials Ministry of EducationWuhan 430072China

CO_(2) electrochemical reduction(CO_(2)ER)is an important research area for carbon ***,available catalysts for CO_(2) reduction are still characterized by limited stability and ***,metallic bismuth(Bi)has emerged as a promising catalyst for CO_(2) ***,we report the solid cathode electroreduction of commercial micronized Bi2O3as a straightforward approach for the preparation of nanostructured ***-1.1 V versus reversible hydrogen electrode in a KHCO3aqueous electrolyte,the resulting nanostructure Bi delivers a formate current density of~40 mA·cm^(-2) with a current efficiency of~86%,and the formate selectivity reaches97.6% at-0.78 *** nanosized Bi2O3as the precursor can further reduce the primary particle sizes of the resulting Bi,leading to a significantly increased formate selectivity at relatively low *** high catalytic activity of nanostructured Bi is attributable to the ultrafine and interconnected Bi nanoparticles in the nanoporous structure,which exposes abundant active sites for CO_(2) electrocatalytic reduction.

关键词： bismuth carbon dioxide electrocatalysis formate solid electroreduction

Natural products inspired[3+2]cycloaddition enables efficient construction of hydroxylated tetrahydrofuran acetals and concise syntheses of lignans

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Science China Chemistry 2024年第7期67卷 2306-2313页

作者： Dong-Yue Cai Weiming Shi Zhao-Hui jin Zhi-Xiang Yu jin-Xin Zhao Jian-Min Yue State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China University of Chinese Academy of Sciences Beijing 100049China Beijing National Laboratory for Molecular Sciences(BNLMS) Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationCollege of ChemistryPeking UniversityBeijing 100871China

Mimicking biosynthetic pathways of hongkonoids led to the development of a new Cu(Ⅰ)-catalyzed[3+2]cycloaddition ofα-hydroxyketone andβ-keto enol ethers,affording tetrahydrofuran acetals in a highly diastereoselective manner and 100%atom *** studies on the mechanism disclosed a concerted but asynchronous Michael addition/aldol *** the same importance,this methodology provides a practical biomimetic approach for one-step construction of the dibenzylbutyrolactol lignan backbone starting from two phenyl propane derivatives,opening up a powerful new approach for lignan synthesis,which is showcased by succinct total syntheses of two biologically important aryltetralin-type lignans,β-apopicropodophyllin and *** the mild and operationally simple conditions,the developed chemistry might have a promising prospect in potential industrial applications.

关键词： [3+2]cycloaddition transition-metal catalysis tetrahydrofuran lignans natural products

P_(c)(4457)Interpreted as a J^(P)=1/2+State byd^(0)∧_(c)^(+)(2595)-π^(0)P_(c)(4312)Interaction

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Chinese Physics Letters 2024年第9期41卷 23-27页

作者： jin-Zi Wu jin-Yi Pang Jia-Jun Wu School of Physics Sciences University of Chinese Academy of SciencesBeijing 100049China Columbian College of Arts&Sciences George Washington University80122nd St.NW Washington DC 20052USA College of Science University of Shanghai for Science and TechnologyShanghai 200093China Southern Center for Nuclear-Science Theory Institute of Modern PhysicsChinese Academy of SciencesHuizhou 516000China

P_(c)(4457)has been discovered over five years,but the parity of this particle remains *** propose a new interpretation for P_(c)(4457),which is the state generated from the coupled-channel D^(0)Ac+(2595)andπ^(0)P_(c)(4312)since they can exchange an almost on-shell∑_(c)^(+).In this scenario,the parity of P_(c)(4457)will be positive,which is different from the candidate of the bound state of D*∑_(c).The main decay channel of P_(c)(4457)in this model is Pc(4312)π.We propose three processes∧_(b)^(0)→J/ψKapπ^(-),∧_(b)^(0)→J/ψK-pπ^(0),and∧_(b)^(0)→J/ψpπ^(-)π^(+)k^(-)to verify Pc(4457)→Pc(4312)π.

关键词： (0 parity verify

THE SUPERCLOSENESS OF THE FINITE ELEMENT METHOD FOR A SINGULARLY PERTURBED CONVECTION-DIFFUSION PROBLEM ON A BAKHVALOV-TYPE MESH IN 2D

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Acta Mathematica Scientia 2024年第4期44卷 1572-1593页

作者： Chunxiao ZHANG jin ZHANG School of Mathematics and Statistics Shandong Normal UniversityJinan 250014China

For singularly perturbed convection-diffusion problems,supercloseness analysis of the finite element method is still open on Bakhvalov-type meshes,especially in the case of *** difficulties arise from the width of the mesh in the layer adjacent to the transition point,resulting in a suboptimal estimate for *** analysis techniques cannot handle these difficulties *** fill this gap,here a novel interpolation is designed delicately for the smooth part of the solution,bringing about the optimal supercloseness result of almost order 2 under an energy norm for the finite element *** theoretical result is uniform in the singular perturbation parameterεand is supported by the numerical experiments.

关键词： singularly perturbed convection-diffusion finite element method supercloseness Bakhvalov-type mesh

A new method of calculating crown projection area and its comparative accuracy with conventional calculations for asymmetric tree crowns

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Journal of Forestry Research 2024年第4期35卷 171-188页

作者： Mingrui Zhang Huiquan Bi Xingji jin Michael McLean School of Forestry Northeast Forestry UniversityHarbin 150040People’s Republic of China Forest Science NSW Department of Primary IndustriesLevel 304PSQ12 Darcy StreetParramattaNSW 2150Australia School of Ecosystem and Forest Sciences The University of MelbourneMelbourne 3010Australia

This paper introduces a new method of calculating crown projection area(CPA),the area of level ground covered by a vertical projection of a tree crown from measured crown radii through numerical interpolation and *** novel method and other four existing methods of calculating CPA were compared using detailed crown radius measurements from 30 tall trees of Eucalyptus pilularis variable in crown size,shape,and *** four existing methods included the polygonal approach and three ways of calculating CPA as the area of a circle using the arithmetic,geometric and quadratic mean *** were made across a sequence of eight non-consecutive numbers(from 2 to 16)of measured crown radii for each tree over the range of crown asymmetry of the 30 trees through generalized linear models and multiple comparisons of *** sequence covered the range of the number of crown radii measured for calculating the CPA of a tree in the literature.A crown asymmetry index within the unit interval was calculated for each tree to serve as a normative *** a slight overestimation of 2.2%on average and an overall mean error size of 7.9%across the numbers of crown radii that were compared,our new method was the least biased and most *** CPA as a circle using the quadratic mean crown radius was the second best,which had an average overestimation of 4.5%and overall mean error size of 8.8%.These two methods remained by and large unbiased as crown asymmetry increased,while the other three methods showed larger bias of *** the conventional method of using the arithmetic mean crown radius to calculate CPA as a circle,bias correction factors were developed as a function of crown asymmetry index to delineate the increasing magnitude of bias associated with greater degrees of crown *** study reveals and demonstrates such relationships between the accuracy of CPA calculations and crown asymmetry and will help increase awa

关键词： Crown radius measurements Interpolated crown contour Projected crown area Multiple comparisons of means

Quantum advantages for image filtering on images with efficient encoding and lower-bounded signal-to-noise ratio

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Science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 2-12页

作者： Zidong Cui Shan jin Akira Sone Xiaoting Wang Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610051China Key Laboratory of Quantum Physics and Photonic Quantum Information Ministry of EducationUniversity of Electronic Science and Technology of ChinaChengdu 611731China Department of Physics University of MassachusettsBoston 02125USA

Quantum image processing has long been a fascinating field,but establishing the existence of quantum speedup for all images remains *** this study,we aim to identify a subset of images for which a quantum algorithm can be developed with a guaranteed ***,we present a quantum image filtering algorithm that exhibits an exponential speedup for efficiently encoded images with a lower-bounded signal-to-noise *** approach relies on a fixed-point Grover's search to emulate the effect of Hadamard multiplication with the filtering *** demonstrate its effectiveness,we apply our method to three typical filtering ***,we emphasize the significance of the efficient-encoding assumption by illustrating that the quantum speedup may diminish for images lacking efficient *** work underscores the importance of exploring image types and features to realize potential quantum advantages in image processing.

关键词： quantum computing quantum image filtering quantum speedup

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Is Yang-Mills theory unitary in fractional spacetime dimensions?

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 59-64页

作者： Qingjun jin Ke Ren Gang Yang Rui Yu Graduate School of China Academy of Engineering Physics Beijing 100193China School of Physics and Astronomy Sun Yat-Sen UniversityZhuhai 519082China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China International Centre for Theoretical Physics Asia-Pacific Hangzhou 310024China School of Physical Science and Technology Inner Mongolia UniversityHohhot 010021China Beijing Computational Science Research Center Beijing 100193China

We present concrete evidence that Yang-Mills theory exhibits non-unitarity in non-integer spacetime *** violation of unitarity stems from evanescent operators that,while vanishing in four dimensions,are non-zero in general d *** demonstrate that these evanescent operators lead to the emergence of both negative-norm states and complex anomalous dimensions.

关键词： gauge field theories field theories in dimensions other than four renormalization

Nicotinamide adenine dinucleotide treatment confers resistance to neonatal ischemia and hypoxia:effects on neurobehavioral phenotypes

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Neural Regeneration Research 2024年第12期19卷 2760-2772页

作者： Xiaowen Xu Xinxin Wang Li Zhang Yiming jin Lili Li Meifang jin Lianyong Li Hong Ni Division of Brain Science Institute of Pediatric ResearchChildren’s Hospital of Soochow UniversitySuzhouJiangsu ProvinceChina Department of Pediatric Orthopedics Shengjing Hospital of China Medical UniversityShenyangLiaoning ProvinceChina

Neonatal hypoxic-ischemic brain injury is the main cause of hypoxic-ischemic encephalopathy and cerebral ***,there are few effective clinical treatments for neonatal hypoxic-ischemic brain ***,we investigated the neuroprotective and molecular mechanisms of exogenous nicotinamide adenine dinucleotide,which can protect against hypoxic injury in adulthood,in a mouse model of neonatal hypoxic-ischemic brain *** this study,nicotinamide adenine dinucleotide(5 mg/kg)was intraperitoneally administered 30 minutes befo re surgery and every 24 hours *** results showed that nicotinamide adenine dinucleotide treatment improved body weight,brain structure,adenosine triphosphate levels,oxidative damage,neurobehavioral test outcomes,and seizure threshold in experimental *** mass tag proteomics revealed that numerous proteins were altered after nicotinamide adenine dinucleotide treatment in hypoxic-ischemic brain injury *** reaction monitoring and western blotting confirmed changes in the expression levels of proteins including serine(or cysteine)peptidase inhibitor,clade A,member 3N,fibronectin 1,5'-nucleotidase,cytosolic IA,microtubule associated protein 2,and complexin *** analyses showed that nicotinamide adenine dinucleotide ameliorated hypoxic-ischemic injury through inflammation-related signaling pathways(e.g.,nuclear factor-kappa B,mitogen-activated protein kinase,and phosphatidylinositol 3 kinase/protein kinase B).These findings suggest that nicotinamide adenine dinucleotide treatment can improve neurobehavioral phenotypes in hypoxic-ischemic brain injury mice through inflammation-related pathways.

关键词： brain injury cerebral palsy hypoxia hypoxic-ischemic brain injury inflammation neuroprotection nicotinamide adenine dinucleotide neonate nicotinamide adenine dinucleotide proteomics

Mechanisms of liver injuries caused by traditional Chinese medicines

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Hepatobiliary & Pancreatic Diseases International 2024年第3期23卷 310-312页

作者： Shui-Fang jin Qi Pan jin-Peng Zhou Xiao-Ping Pan Intensive Care Unit The First Affiliated Hospital of Zhejiang Chinese Medical University(Zhejiang Provincial Hospital of Chinese Medicine)Hangzhou 310006China Institute of Liver Diseases College of Basic Medical SciencesZhejiang Chinese Medical UniversityHangzhou 310053China The Second Clinical Medical College of Zhejiang Chinese Medical University Hangzhou 310056China

Drug-induced liver injury(DILI)is a common adverse drug reaction,which can even result in liver failure[1,2].The Chinese Medical Association issued the Guidelines for the Diagnosis and Treatment of DILI based on the Roussel Uclaf Causality Assessment Method(RUCAM)in 2015[3].A previous study reported that traditional Chinese medicines(TCMs),herbal and dietary supplements,and antituberculosis drugs were the main causes of DILI in China[4].Herb-induced liver injury(HILI)refers to liver injury caused by TCMs,natural drugs,and their related preparations[5].

关键词： drugs tuberculosis TCM

Optimizing mechanical properties of HIPS fabricated with low-cost desktop 3D printers:investigating the impact of process parameters

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Advances in Manufacturing 2024年第2期12卷 379-395页

作者： jin-Ting Xu Guang-Wei Zhang Man-Man Chen School of Automotive Engineering Dalian University of TechnologyDalian116024People’s Republic of China

Recently,low-cost desktop three-dimensional(3D)printers,employing the fused deposition modeling(FDM)technique,have gained widespread ***,most users cannot test the strength of printed parts,and little information is available about the mechanical properties of printed high-impact polystyrene(HIPS)parts using desktop 3D *** this study,the user-adjustable parameters of desktop 3D printers,such as crisscross raster orientation,layer thickness,and infill density,were *** experimental plans were designed using the Box-Behnken method,and tensile,3-point bending,and compression tests were carried out to determine the mechanical responses of the printed *** prediction models of the process parameters were regressed to produce the optimal combination of process *** experimental results showcase that the crisscross raster orientation has significant effects on the flexural and compression strengths,but not on the tensile *** an increase in the layer thickness,the tensile,flexural,and compression strengths first decreased and then increased,reaching their minimum values at approximately 0.16 mm layer *** addition,they all increased with an increase of infill *** was demonstrated that when the raster orientation,layer thickness,and infill density were 13.08°/–76.92°,0.09 mm,and 80%,respectively,the comprehensive mechanical properties of the printed HIPS were *** results can help end-users of desktop 3D printers understand the effects of process parameters on the mechanical properties,and offer practical suggestions for setting proper printing parameters for fabricating HIPS parts.

关键词： Desktop three-dimensional(3D)printers Fused deposition modeling(FDM) High-impact polystyrene(HIPS) Process parameters