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electron-phonon coupling and spin fluctuations in the Ising superconductor NbSe_(2)

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npj Computational Materials 2023年第1期9卷 1686-1694页

作者： S.Das H.Paudyal e.R.Margine D.F.Agterberg I.I.Mazin Department of Physics and Astronomy George Mason UniversityFairfaxVA 22030USA Quantum Science and engineering Center George Mason UniversityFairfaxVA 22030USA Department of Physics Applied Physicsand AstronomyBinghamton University-SUNYBinghamtonNY 13902USA Department of Physics University of WisconsinMilwaukeeWI 53201USA

Ising superconductivity,observed in NbSe2 and similar materials,has generated tremendous ***,attention was called to the possible role that spin fluctuations(SF)play in this phenomenon,in addition to the dominant electron–phonon coupling(ePC);the possibility of a predominantly triplet state was discussed and led to a conjecture of viable singlet–triplet Leggett ***,these hypotheses have not been put to a quantitative *** this paper,we report first principle calculations of the ePC and also estimate coupling with SF,including full momentum *** find that:(1)ePC is strongly anisotropic,largely coming from the K-K0 scattering,and therefore excludes triplet symmetry even as an excited state;(2)superconductivity is substantially weakened by SF,but anisotropy remains as above;and,(3)we do find the possibility of a Leggett mode,not in a singlet–triplet but in an s_(++)–s_(±)channel.

关键词： coupling phonon superconductivity

PRISMS-Fatigue computational framework for fatigue analysis in polycrystalline metals and alloys

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npj Computational Materials 2021年第1期7卷 349-360页

作者： Mohammadreza Yaghoobi Krzysztof S.Stopka Aaditya Lakshmanan Veera Sundararaghavan John e.Allison David L.McDowell Materials Science and engineering University of MichiganAnn ArborMIUSA Woodruff School of Mechanical engineering Georgia Institute of TechnologyAtlantaGAUSA Aerospace engineering University of MichiganAnn ArborMIUSA School of Materials Science and engineering Georgia Institute of TechnologyAtlantaGAUSA

The PRISMS-Fatigue open-source framework for simulation-based analysis of microstructural influences on fatigue resistance for polycrystalline metals and alloys is presented *** framework uses the crystal plasticity finite element method as its microstructure analysis tool and provides a highly efficient,scalable,flexible,and easy-to-use ICMe community *** PRISMS-Fatigue framework is linked to different open-source software to instantiate microstructures,compute the material response,and assess fatigue indicator *** performance of PRISMS-Fatigue is benchmarked against a similar framework implemented using *** indicate that the multilevel parallelism scheme of PRISMS-Fatigue is more efficient and scalable than ABAQUS for large-scale fatigue *** performance and flexibility of this framework is demonstrated with various examples that assess the driving force for fatigue crack formation of microstructures with different crystallographic textures,grain morphologies,and grain numbers,and under different multiaxial strain states,strain magnitudes,and boundary conditions.

关键词： fatigue alloys grain

基于区块链的电网安稳控制通信报文记录与审计系统研究

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计算机应用与软件 2024年第4期41卷 112-118页

作者：颜云松陈汹于同伟封科李俊娥王永余发江赵思宇国网电力科学研究院有限公司江苏南京211000 东南大学电气工程学院江苏南京210096 东北电力大学吉林吉林132012 国网辽宁省电力有限公司电力科学研究院辽宁沈阳110000 空天信息安全与可信计算教育部重点实验室武汉大学国家网络安全学院湖北武汉430072

随着电网安全稳定控制系统向广域化、复杂化方向发展,安稳控制通信报文数量多,通信链条长,易被篡改。当通信报文异变或损坏导致安控系统发生误动或拒动时,难以准确判断事故原因。针对该问题,提出一个基于区块链的电网安稳控制通信报文... 详细信息

随着电网安全稳定控制系统向广域化、复杂化方向发展,安稳控制通信报文数量多,通信链条长,易被篡改。当通信报文异变或损坏导致安控系统发生误动或拒动时,难以准确判断事故原因。针对该问题,提出一个基于区块链的电网安稳控制通信报文记录与审计系统。基于安控系统架构与管理需求设计半中心化系统模型,并针对安控系统架构与业务特点设计交叉多链结构。实验结果表明,该方案能够提高安稳控制通信报文记录与审计的真实性、完整性和安全性,同时具有较好的性能。

关键词：安全稳定控制系统区块链通信报文记录与审计半中心化系统模型交叉多链结构

Application of thermally stimulated acoustic emission method to assess the thermal resistance and related properties of coals

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International Journal of Mining Science and Technology 2018年第2期28卷 243-249页

作者： e.A.Novikov R.O.Oshkin V.L.Shkuratnik S.A.epshtein N.N.Dobryakova National University of Science and Technology(MISiS) Moscow 119049Russia

Traditional methods of coal thermal resistance characterization are informative but considerably timeconsuming and require utilization of a complex and expensive equipment. This limits the effectiveness of their application. In this paper, authors experimentally investigated potential application of thermally stimulated acoustic emission method for developing of relatively simple and rapid coals thermal resistance assessment method. Features of thermally stimulated acoustic emission of anthracite, lignites and bituminous coal samples subject to cyclic thermal loading have been experimentally *** the first time, it has been shown that there exists a relationship of such patterns with structural parameters and properties of the coal samples, as well as their thermal resistance. The results indicate the possibility of applying the method of thermally stimulated acoustic emission to control processes of cryogenic disintegration and thermal resistance of fossil coals. The description of the equipment and methodological support needed for the implementation of this method have been provided.

关键词： Acoustic emission Fossil coal Thermal resistance Cryogenic disintegration Structure Properties

Localized dissolution initiated at single and clustered intermetallic particles during immersion of Al-Cu-Mg alloy in sodium chloride solution

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Transactions of Nonferrous Metals Society of China 2016年第11期26卷 2800-2809页

作者：骆晨 Xiaorong ZHOU George e.THOMPSON 中航工业北京航空材料研究院航空材料先进腐蚀与防护航空科技重点实验室北京100095 School of Materials The University of Manchester

Aiming at understanding how intermetallic phases response when AA2024-T3 aluminium alloy is exposed to chloridecontainingaqueous medium, scanning electron microscopy was employed to provide morphological information on alloy surfacebefore and after corrosion testing. energy dispersive X-ray spectroscopy was carried out to determine compositional change inintermetallic particles. Atomic force microscopy was used to examine topographical variation introduced by the reactions ofintermetallic phases. Transmission electron microscopy combined with ultramicrotomy was carried out on dealloyed Al2CuMgparticles and their periphery region. It is found that dealloyed Al2CuMg particles exhibited porous, polycrystalline structurecomprised of body-centred cubic copper particles with sizes of 5 to 20 nm. Aluminium matrix started to trench in the periphery ofAl2CuMg particles at the early stage of dealloying. Development of trenching in ***.（Si） particle’s periphery was notuniform and took longer time to initiate than Al2CuMg dealloying. Localized corrosion at a cluster of Al2CuMg and Al2Cu particleswas mainly associated with Al2CuMg particles.

关键词： aluminium alloy intermetallic particle localized dissolution dealloying trenching

A value adding approach to hard-rock underground mining operations: Balancing orebody orientation and mining direction through meta-heuristic optimization

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Journal of Central South University 2019年第11期26卷 3126-3139页

作者： Martha e.VILLALBA MATAMOROS Mustafa KUMRAL Department of Mining and Materials engineering Mc Gill University

Underground mines require complex construction activities including the shaft, levels, raises, winzes and ore passes. In an underground mine based on stoping method, orebody part(s) maximizing profit should be determined. This process is called stope layout optimization (SLO) and implemented under site-specific geotechnical, operational and economic constraints. For practical purpose, the design obtained by SLO shows consecutive stopes in one path, which assists in defining the mining direction of these stopes. However, this direction may not accommodate the spatial distribution of the ore grade: if the orebody orientation and mining direction differ, the value of the mining operation may decrease. This paper proposes an approach whereby paths in the SLO are defined as decision variables to avoid the cost of mining in the wrong direction. Furthermore, in the genetic-based formulation, which accounts for orebody uncertainty, a robust cluster average design process is proposed to improve SLO’s performance regarding metal content. A case study in narrow gold vein deposit shows that the profit of an underground mining operation could be underestimated by 25%-48% if the algorithm ignores stope layout orientation.

关键词： underground mine planning orebody uncertainty orebody orientation mining direction stope layout optimization

Logopenic变异型原发性进行性失语病例报道1例

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阿尔茨海默病及相关病杂志 2024年第1期7卷 35-39页

作者：叶青青乐欢唐娥刘净娇刘庆贵州省贵阳市第二人民医院(金阳医院)/贵州医科大学附属金阳医院贵阳550000

目的:Logopenic变异型原发性进行性失语(logopenic variant primary progressive aphasia,lvPPA)临床较为少见,大部分lvPPA与阿尔茨海默病(Alzheimer's disease,AD)具有典型的病理改变,相较以记忆障碍起病的典型AD,以非遗忘综合征起病的不典型AD容易被误诊或漏诊。分享1例以非流利型口语障碍为首发症状的不典型AD-Logopenic变异型原发性进行性失语患者,以期为临床医生提供非典型AD的临床诊治经验。方法:报告1例非典型阿尔茨海默病lvPPA患者的临床、影像学、实验室检查等特点,并结合文献进行复习。结果:早非典型AD-Logopenic变异型原发性进行性失语主要表现为早期出现的自发语言和命名过程中单个词语的取词困难及语句复述能力下降。详细地询问病史,体格检查,及生物标记物的检测、PeT或基因检测可助于早期诊断。

关键词：原发性进行性失语症非典型阿尔茨海默病临床特点言语障碍神经影像诊断标准

An assessment of steady-state conditions in single slug horizontal pneumatic conveying

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Particuology 2021年第5期19卷 187-195页

作者： A.Lavrinec O.Orozovic H.Rajabnia K.Williams M.G.Jones G.e.Klinzing Centre for Bulk Solids and Particulate Technologies The University of NewcastleNSW 2308Australia Department of Chemical and Petroleum engineering The University of PittsburghPA 15261USA

This study used a 3D coupled CFD–DeM model to assess how slugs tend towards steady state in single slug horizontal pneumatic *** slug length,inlet velocity and initial stationary layer fractions were systematically varied for a total of 72 *** made observation that slugs tend towards a steady state was confirmed via a theoretical *** derivation shows that slugs move towards their steady state lengths *** allowed for a calculation of a characteristic time scale which is a measure of how quickly a slug tends towards the steady *** theoretical estimate which is a function of slug porosity,steady length,velocity and stationary layer fraction has good agreement with simulated results.A link between steady slug length and solids loading ratio was also shown.

关键词： Pneumatic conveying Dense phase Slug flow Steady state

Titanium oxide artificial synaptic device:Nanostructure modeling and synthesis,memristive cross-bar fabrication,and resistive switching investigation

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Nano Research 2023年第7期16卷 10222-10233页

作者： Vadim I.Avilov Roman V.Tominov Zakhar e.Vakulov Lev G.Zhavoronkov Vladimir A.Smirnov Research Laboratory Neuroelectronics and Memristive Nanomaterials(NeUROMeNA Lab) Southern Federal UniversityTaganrog 347922Russia Institute of Nanotechnologies Electronics and Electronic Equipment EngineeringSouthern Federal UniversityTaganrog 347922Russia

The paper shows the results of the mathematical model development and the numerical simulation of the oxygen vacancies,and the distribution of TiO,Ti_(2)O_(3),and TiO_(2)oxides in the titanium oxide nanostructure obtained by local anodic oxidation(anodization).The effect of the anodization voltage pulse duration and amplitude on the titanium oxide composition distribution and the conduction channel formation was *** device prototypes based on electrochemical titanium oxide are fabricated and *** was shown that forming free resistive switching between the low resistances state(LRS)1.43±0.54 kΩand the high resistance state(HRS)28.75±9.75 kΩwere observed during 100,000 switching cycles and LRS 1.49±0.23 kΩwas maintained for 10,000 *** resistive switching of the synaptic device prototype was *** was shown that increasing Uset from 0.5 to 1.5 V leads to different LRS from 3.96±0.19 to 0.71±0.10 kΩ.The results obtained can be used in the development of technological foundations for the formation of high-performance multilevel artificial synapses for elements of neuroelectronics and hardware neural networks.

关键词： artificial intelligence neuromorphic systems memristive cross bar resistive switching scanning probe microscopy titanium oxide