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Electron drift velocity and mobility in graphene

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Frontiers of physics 2018年第2期13卷 153-157页

作者： Hai-ming Dong yi-Feng Duan Fei huang Jin-Long Liu School of Physical Science and Technology China University of Mining and Technology Xuzhou 221116 China Low Carbon Energy Institute China University of Mining and Technology Xuzhou 221116 China School of Materials Science and Engineering China University of Mining and Technology Xuzhou 221116 China

We present a theoretical study of the electric transport properties of graphene-substrate systems. The drift velocity, mobility, and temperature of the electrons are self-consistently determined using the Boltzmann equilibrium equations. It is revealed that the electronic transport exhibits a distinctly nonlinear behavior. A very high mobility is achieved with the increase of the electric fields increase. The electron velocity is not completely saturated with the increase of the electric field. The temperature of the hot electrons depends quasi-linearly on the electric field. In addition, we show that the electron velocity, mobility, and electron temperature are be employed for the application of graphene for sensitive to the electron density. These findings could high-field nano-electronic devices.

关键词： graphene mobility nano-electronic devices

Mechanical Property Prediction of Strip Model Based on PSO-BP Neural Network

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Journal of Iron and Steel Research International 2008年第3期15卷 87-91页

作者： WANG Ping huang Zhen-yi ZHANG ming-ya ZHAO Xue-wu School of Metallurgy and Materials Anhui University of Technology Ma＇anshan 243002 Anhui China Anhui Key Laboratory of Metal Materials and Processing Ma＇anshan 243002 Anhui China Zhangjiagang Pohang Stainless Steel Co Ltd Zhangjiagang 215000 Jiangsu China

Mechanical property prediction of hot rolled strip is one of the hotspots in material processing research. To avoid the local infinitesimal defect and slow constringency in pure BP algorithm, a kind of global optimization algorithm-particle swarm optimization （PSO） is adopted. The algorithm is combined with the BP rapid training algorithm, and then, a kind of new neural network （NN） called PSO-BP NN is established. With the advantages of global optimization ability and the rapid constringency of the BP rapid training algorithm, the new algorithm fully shows the ability of nonlinear approach of multilayer feedforward network, improves the performance of NN, and provides a favorable basis for further online application of a comprehensive model.

关键词： particle swarm optimization algorithm BP neural network hot continuous rolling strip mechanical property prediction

Effects of shear stress on differentiation of stem cells into endothelial cells

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World Journal of Stem Cells 2021年第7期13卷 894-913页

作者： Yan huang Jia-yi Qian Hong Cheng Xiao-ming Li Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education Beijing Advanced Innovation Center for Biomedical EngineeringSchool of Biological Science and Medical EngineeringBeihang UniversityBeijing 100083China

Stem cell transplantation is an appealing potential therapy for vascular diseases and an indispensable key step in vascular tissue *** effort has been made to differentiate stem cells toward vascular cell phenotypes,including endothelial cells(ECs)and smooth muscle *** microenvironment of vascular cells not only contains biochemical factors that influence differentiation but also exerts hemodynamic forces,such as shear stress and cyclic *** recently,studies have shown that shear stress can influence the differentiation of stem cells toward ECs.A deep understanding of the responses and underlying mechanisms involved in this process is essential for clinical *** review highlights current data supporting the role of shear stress in stem cell differentiation into *** mechanisms and signaling cascades for transducing shear stress into a biological signal are *** study of stem cell responses to shear stress will be necessary to apply stem cells for pharmacological applications and cardiovascular implants in the realm of regenerative medicine.

关键词： Shear stress Stem cells Cell differentiation Endothelial cells Mechanotransduction

XRD Analysis on the Fluorescence Material of Sm Doped Si-Ca-Mg System

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Chinese Journal of Structural Chemistry 2007年第8期26卷 902-906页

作者： huang Qing-ming Instrumentation Analysis and Measurement Center of Fuzhou University Fuzhou Fujian 350002 China

Fluorescence material of Sm doped Si-Ca-Mg system was synthesized by using the method of solid phase reaction at high temperature. The phase composition and crystal structure of this material were analyzed with XRD method for its composition and the existence form of Sm atom. We aimed to exactly determine the phase composition of this fluorescence material and the doping position and environment of rare-earth Sm atom in the system because these factors have significant effects on the properties. The analytical results show that the Sm atoms dope in Ca2O26Si6Sm8 lattice in the form of atomic site-occupation in three different space positions with different occupancy rates. Therefore, based on the XRD analytical results, the fluorescence material of Sm doped Si-Ca-Mg system with high performance can be synthesized.

关键词： XRD fluorescence material Sm structure

D2ANet:Difference-aware attention network for multi-level change detection from satellite imagery

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Computational Visual Media 2023年第3期9卷 563-579页

作者： Jie Mei yi-Bo Zheng ming-ming Cheng TMCC CSNankai UniversityTianjin 300350China State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China

Recognizing dynamic variations on the ground,especially changes caused by various natural disasters,is critical for assessing the severity of the damage and directing the disaster ***,current workflows for disaster assessment usually require human analysts to observe and identify damaged buildings,which is labor-intensive and unsuitable for large-scale disaster *** this paper,we propose a difference-aware attention network(D2ANet)for simultaneous building localization and multi-level change detection from the dual-temporal satellite *** the differences in different channels in the features of pre-and post-disaster images,we develop a dual-temporal aggregation module using paired features to excite change-sensitive channels of the features and learn the global change *** the nature of building damage caused by disasters is diverse in complex environments,we design a difference-attention module to exploit local correlations among the multi-level changes,which improves the ability to identify damage on different *** experiments on the large-scale building damage assessment dataset xBD demonstrate that our approach provides new state-of-the-art *** code is publicly available at https://***/mj129/D2ANet.

关键词： change detection building localization sate-llite imagery dual-temporal aggregation difference attention

Clinical characteristics and in-hospital outcomes of patients receiving contemporary intensive cardiac care:retrospective study from a large centre in China

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Journal of Geriatric Cardiology 2021年第2期18卷 94-103页

作者： Fei CHEN yi-ming LI Qi LIU Bao-Tao huang Fang-Yang huang Yong PENG Mao CHEN Department of Cardiology West China HospitalSichuan UniversityChengduChina West China School of Medicine Sichuan UniversityChengduChina

BACKGROUND Few studies from developed countries have quantitatively characterized the clinical characteristics and outcomes of patients receiving contemporary intensive cardiac *** sought to investigate these data in patients admitted to a Chinese intensive cardiac care unit(ICCU).METHODS We conducted a retrospective study using data from 2,337 consecutive admissions to the ICCU at a large centre in China from June 2016 to May *** were captured after systematic inspection of individual medical records regarding current demographics,primary diagnosis,comorbidities,illnesses severity,and in-hospital *** The mean age was 65.6±14.2 years,and females accounted for 32.0%of *** Charlson Comorbidity Index and Oxford Acute Severity of Illness Score were 2.4±1.8 and 22.5±10.4,*** top reason for admission was ST-segment elevation myocardial infarction(32.0%),and nonischaemic heart diseases accounted for 31.2%of all primary *** diseases were prevalent in the ICCU population,including chronic illnesses and acute noncardiovascular critical illnesses(ANCIs);in particular,21.7%of patients were marked by acute respiratory failure(14.6%),acute kidney injury(13.7%),sepsis(4.2%),or gastrointestinal bleeding(3.3%).The median length of stay in the ICCU and hospital were 1.1 days[interquartile range(IQR):0.8–2.6 days]and 6.3 days(IQR:3.8−10.9 days),*** overall incidence of in-hospital death or discharge against medical advice under extremely critical conditions was 7.6%(n=177).Multivariate logistic regression analysis showed that the complexity of chronic illnesses and incident ANCIs were strong independent determinants for in-hospital *** Remarkable patient diversity and breadth of critical illnesses were observed in a Chinese ICCU ***,noncardiovascular diseases were prevalent and associated with adverse *** of organization and staffing practices may be

关键词： patients admitted centre

Mechanisms Causing Ballistic Thermal Rectification

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Chinese Physics Letters 2014年第4期31卷 118-121页

作者： DING Xing ming yi School of Physics and Material Science Anhui University Hefei 230601

The mechanism causing the ballistic thermal rectification in the harmonic system is analytically studied. Using the conceptual model of a dephasing probe, we obtain that phase breaking is unnecessary to realize the ballistic thermal rectification. However, it can change the strength of rectification. Asymmetric phonon-phonon interac- tion inducing the energy exchange of the normal mode of vibration is necessary to realize the ballistic thermal rectification. Moreover, the quantum statistics of phonons in at least one thermal reservoir is crucial to guarantee the asymmetric phonon-phonon interaction.

关键词： Rectification Mechanisms ballistic

Convergence in Conformal Field Theory

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Chinese Annals of Mathematics,Series B 2022年第6期43卷 1101-1124页

作者： yi-Zhi huang Department of Mathematics Rutgers UniversityPiscatawayNJ 08854USA

Convergence and analytic extension are of fundamental importance in the mathematical construction and study of conformal field *** author reviews some main convergence results,conjectures and problems in the construction and study of conformal field theories using the representation theory of vertex operator *** also reviews the related analytic extension results,conjectures and *** discusses the convergence and analytic extensions of products of intertwining operators(chiral conformal fields)and of q-traces and pseudo-q-traces of products of intertwining *** also discusses the convergence results related to the sewing operation and the determinant line bundle and a higher-genus convergence *** then explains conjectures and problems on the convergence and analytic extensions in orbifold conformal field theory and in the cohomology theory of vertex operator algebras.

关键词： Conformal field theory Vertex operator algebras Representation theory Convergence Analytic extension

HS-SPME结合GC-O-MS技术分析不同大曲中的香气活性化合物

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食品工业科技 2017年第6期38卷 54-61,78页

作者：孟维一黄明泉孙宝国郑福平孙金沅孙啸涛李贺贺北京市食品风味化学重点实验室北京工商大学北京100048 食品质量与安全北京实验室北京工商大学北京100048

通过顶空-固相微萃取(HS-SPME)结合气相色谱-嗅闻-质谱(GC-O-MS)联用技术,研究了大曲的香气成分,同时考察了萃取头、萃取时间、萃取温度和样品量对大曲样品中挥发性成分分析的影响。结果表明:取1.5 g样品在50℃下平衡10 min后,用50/30μ... 详细信息

通过顶空-固相微萃取(HS-SPME)结合气相色谱-嗅闻-质谱(GC-O-MS)联用技术,研究了大曲的香气成分,同时考察了萃取头、萃取时间、萃取温度和样品量对大曲样品中挥发性成分分析的影响。结果表明:取1.5 g样品在50℃下平衡10 min后,用50/30μm DVB/CAR/PDMS纤维萃取头在50℃下萃取30 min,萃取效果较好;在此条件下分析大曲样品,7种大曲中共检出69种挥发性成分,包括醇类9种、酯类13种、醛类8种、酮类4种、酸类3种、吡嗪类9种、芳香族类8种、酚类5种、杂环类2种、烷烃类3种和其他类5种;采用GC-O-MS检出17种为香气活性化合物,定性出14种化合物,其中2-乙基-3,5-二甲基吡嗪、苯乙醛是OAV值较大且香气强度较大的香气活性化合物,贡献了烤土豆香、蜂蜜香、甜香,综合组成了大曲独特的风味。

关键词：大曲顶空-固相微萃取气相色谱-嗅闻-质谱风味活性化合物香气活性值