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A path integral approach to electronic friction of a nanometer-sized tip scanning a metal surface

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Communications in Theoretical Physics 2021年第4期73卷 111-120页

作者： Yang Wang yu jia School of Physics Zhengzhou UniversityZhengzhou 450001China International Laboratory for Quantum Functional Materials of Henan and School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450001China Key Laboratory for Special Functional Materials of Ministry of Education and School of Materials and EngineeringHenan UniversityKaifeng475001China

In this work,we study the dissipation mechanism and frictional force of a nanometer-sized tip scanning a metal surface via a path integral *** metal,with internal degrees of freedom(c,c^(†))and a tip with an internal degree of freedom(d,d^(†))couple with one another by means of an exchanged potential,*** integrated out all internal degrees of freedom,we obtain the in-out ***,we calculate the imaginary part of the in-out amplitude and the frictional *** find the imaginary part of the in-out amplitude to be positive,and correlated to the sliding velocity in most *** frictional force is proportional to the sliding velocity for the case where v0.01,the frictional force demonstrates nonlinear dependence on sliding velocity.

关键词： path integral electronic friction quantum field

NUMERICAL INVESTIGATION OF SEABED INTERACTION IN TIME DOMAIN ANALYSIS OF MOORING CABLES

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Journal of Hydrodynamics 2006年第4期18卷 424-430页

作者： yu Long TAN jia-hua School of Naval Architecture and Civil Engineering Shanghai Jiaotong University Shanghai 200030 China

In this paper, an efficient two-dimensional finite element model for numerical analysis of mooring cables and seabed interaction has been built. Geometric shape and dynamics of mooring cables are computed in time domain, accounting for the motions of the moored sturcture. In the model, a hybrid beam element is employed to simulate the mooring cable while the seabed is simulated by application of different soil constitutive models. After the elastic and elastic-plastic soil constitutive models have been used for computation, tensions and offsets of mooring cables at fairlead point are also compared accounting for friction effect between cables and seabed. Both transversal and longitudinal behaviors are studied at different water depths.

关键词： dynamics of mooring cable seabed interaction soil constitutive models

Rational design and synthesis of advanced metal-organic frameworks for electrocatalytic water splitting

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Science China Chemistry 2023年第4期66卷 943-965页

作者： yu-jia Tang Ya-Qian Lan School of Chemistry and Materials Science Institute of Advanced Materials and Flexible Electronics(IAMFE)Nanjing University of Information Science and TechnologyNanjing 210044China School of Chemistry South China Normal UniversityGuangzhou 510006China

As a promising and significant technology for hydrogen production,electrocatalytic water splitting is a research hotspot in the energy conversion field for alleviating the global energy crisis and achieving carbon neutrality ***-organic frameworks(MOFs)have been widely investigated as catalyst candidates with remarkable activity and long-term electrocatalysis durability owing to their precise and tailorable structures:tunable pore channels in the range of micropore/mesopore promote the mass/electron transfer;high specific surface areas expose abundant active species;modified metal nodes can serve as active sites;versatile organic ligands can be functionalized to further enhance the electrocatalytic *** this review,recent advances in the rational design and synthesis of advanced MOF electrocatalysts for water splitting are presented in the following ***,we analyze the design concepts of MOF electrocatalysts from the perspective of their distinct and modifiable ***,three common synthesis techniques of MOF electrocatalysts are briefly ***,we focus on the classification of different MOFs for robust electrocatalytic water splitting,including pristine MOFs,mixed-metallic MOFs,MOF nanosheets,electrically conductive MOFs,MOFs on substrates,and polyoxometalate-based ***,summary and outlook are proposed to uncover the next generation of advanced MOFs for electrochemical energy conversion applications.

关键词： metal-organic frameworks water splitting electrocatalysis hydrogen evolution reaction oxygen evolution reaction polyoxometalates

Multi-criteria Satisfaction Assessment of the Spatial Distribution of Urban Emergency Shelters Based on High-Precision Population Estimation

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International Journal of Disaster Risk Science 2016年第4期7卷 413-429页

作者： jia yu jiahong Wen Department of Geography Shanghai Normal University

This article introduces a framework for the multi-criteria satisfaction assessment of the spatial distribution of urban emergency shelters.A GIS-based analytic hierarchy process approach was utilized to conduct the assessment based on selected criteria layers for daytime and nighttime scenarios,*** layers were generated from high-precision land use data based on highresolution aerial images and census *** the uncertainty in criteria weighting,a spatial sensitivity analysis was undertaken for deriving more accurate *** feasibility of the framework was tested on a case study in Jing'an District,Shanghai,*** assessment results show that both at nighttime and during daytime,even if all potentially available shelters are open,the demand in large areas can only be marginally satisfied or not satisfied,especially in the northern,eastern,and central parts of Jing'an *** quantitative analysis of the satisfaction conditions of the buildings or land parcels and the affected people,especially children and the elderly,shows a low satisfaction level of shelter services in these *** satisfaction assessment of emergency shelters can help government decision makers find low satisfaction areas of sheltering services and support further locationallocation optimization of urban emergency shelters.

关键词： Population estimation Shanghai Spatial distribution Urban emergency shelters

Large isolated fibrous tumors in the upper esophagus: A case report

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World Journal of Gastrointestinal Oncology 2024年第2期16卷 543-549页

作者： jia-jia yu Huan-Shuang Pei yu Meng Department of Anesthesiology The Fourth Hospital of Hebei Medical UniversityShijiazhuang 050000Hebei ProvinceChina

BACKGROUND Solitary fibrous tumors(SFT)are rare spindle cell tumors that are usually benign.A total of 10 cases of SFTs in the upper esophagus have ever been ***,we report the anesthetic management of a patient with a large isolated fibrous tumor of the upper esophagus compressing the tracheal *** also provide a literature review of the current *** SUMMARY We report the case of a 49 year old male with“cough aggravation and wheezing after exercise”,who underwent esophagectomy for a large isolated fibrous tumor compressing the tracheal membrane in the upper *** advise the use of a single-lumen tube with a blocker in patients with difficult airways to reduce the incidence of airway injury and fibrinoscopy at all stages of the perioperative period to guide airway *** case study is the first report of the anesthetic management of a large,isolated fibrous tumor compressing the tracheal membrane in the upper *** This rare case emphasizes the importance of perioperative management of anesthesia in patients with large isolated fibrous tumors of the upper esophagus that compress the tracheal *** use of blocker reduce the incidence of airway injury and fibrinoscopy at the perioperative period to guide airway mana-gement.

关键词： Upper esophagus Isolated fibrous tumor Tracheal membrane Peak airway pressure Case report

A taxonomic revision of Ulota Mohr （Orthotrichaceae） in South and Central America

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植物分类与资源学报 2016年第2期38卷 82-109页

作者： QinghuaWang yu jia State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany the Chinese Academy of Sciences Beijing 100093 China

Twenty-three species of Ulota from South and Central America have previously been reported.A revision of the species suggests that number should be reduced to thirteen(***,***,***,***,***,***,***,***,***,***,***,*** and ***) with eight names(*** = ***,*** = ***,*** = ***,*** = ***,*** = ***,*** = ***,*** = *** and *** = ***) reduced to synonyms,as well as three varieties(*** *** = ***,*** *** = *** and *** *** = ***).The taxonomic status of two names(*** and ***) remains *** typification of five names(***,***,***,*** and ***) is proposed *** the first report of *** for South America,the total number of species accepted here for this region is *** species(*** and ***) occur in both Hemispheres,one species(***) is only present in the Northern Hemisphere,whereas the remaining eleven species are all restricted to the Southern *** them,nine(***,***,***,***,***,***,***,*** and ***) are restricted to South America,and two(*** and ***) are distributed in South America and *** peristomes and spores of seven accepted species are illustrated in SEM micrographs.A key to all accepted species as well as descriptions,illustrations,synonyms,ecological and geographic distributions,and discussions are provided.

关键词： Moss Orthotrichaceae South and Central America Taxonomy Ulota

A Cellular Automata Based Verifiable Multi-secret Sharing Scheme Without a Trusted Dealer

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Chinese Journal of Electronics 2017年第2期26卷 313-318页

作者： LI Meng yu jia HAO Rong College of Computer Science and Technology Qingdao University Shandong Provincial Key Laboratory of Computer Network

We proposed a verifiable multi-secret sharing scheme without a *** use cellular automata,having the properties of linear computations and parallel computations,to construct our *** linear computational property makes it possible to build a scheme without the assistance of a trusted dealer,and the parallel computational property contributes to the high efficiency of the *** function is used to realize the verification of shares,which also makes our scheme more *** security of the scheme is also analyzed.

关键词： Multi-secret sharing Verifiability Trusted dealer Cellular automata Hash function

Calculation of radiative heat flux on irregular boundaries in participating media

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Chinese Physics B 2020年第12期29卷 322-328页

作者： yu-jia Sun Shu Zheng School of Atmospheric Physics Nanjing University of Information Science and TechnologyNanjing 210044China National Engineering Laboratory for Biomass Power Generation Equipment North China Electric Power UniversityBeijing 102206China

Radiative heat flux at wall boundaries is important for its thermal *** methods based on structured grids are becoming trendy due to their simplicity and *** radiative transfer equation solvers produce oscillating radiative heat flux at the irregular boundary if they are based on structured *** Monte Carlo method and analytical discrete ordinates method are adopted to calculate the radiative heat flux at complex *** results show that the reverse Monte Carlo method can generate a smooth radiative heat flux profile and it is smoother with larger energy *** results from the analytical discrete ordinates method show that the fluctuations are due to the ray *** the total or the mean radiative heat flux,the results from the analytical discrete ordinates method are very close to those from the reverse Monte Carlo method.

关键词： radiative heat flux reverse Monte Carlo irregular boundary

Progress on asymptotic behavior of the Yang-Mills-Higgs flow

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Applied Mathematics(A Journal of Chinese Universities) 2013年第4期28卷 565-574页

作者： LI jia-yu ZHANG Xi School of Mathematical Sciences University of Science and Technology of China AMSS CAS

In this note we will introduce our recent work on the existence of approximate Hermitian-Einstein structures on semi-stable Higgs bundles, and the asymptotic behavior of the Yang-Mills-Higgs flow for Higgs pairs at in... 详细信息

关键词： Yang-Mills-Higgs flow Higgs bundle Khler manifold