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structure and Properties of Nanostructured Vacuum-Deposited Foils of Invar Fe–(35–38 wt%)Ni Alloys

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Journal of Materials science & Technology 2015年第11期31卷 1079-1086页

作者： V.M.Nadutov A.I.Ustinov s.A.Demchenkov Ye.O.svystunov V.s.skorodzievski G.V.Kurdyumov Institute for Metal Physics of National Academy of sciences of Ukraine E.O.Paton Electric Welding Institute of National Academy of sciences of Ukraine

The process of electron beam vacuum deposition of the Fe-（35-38 wt%）Ni alloys at substrate temperatures ts from 300 to700 ℃ were used to produce vacuum-deposited foils with the FCC structure, differing by the size of characteristic microstructural elements （grains and subgrains）. It was shown that refinement of foil microstructural elements to nanoscale is accompanied by their microhardness increase up to 4-5 GPa. The change of the thermal expansion coefficient （TEC） of the nanostructured （Ns） foil of the Fe-35.1Ni alloy within the temperature range from -50 to 150 ℃ has some deviation from that observed for cast Invar alloy of the same composition. It has been found that the main factors affecting the peculiarities of thermal expansion of the Ns foil can be related to the presence of small fraction of BCC- phase in them, high level of crystalline lattice microstrains and inhomogeneous magnetic order in FCC- phase. It was shown that as a result of additional thermal treatment of Ns foils their invar properties become similar to that observed for cast Invar alloy but mechanical properties remain on the same level.

关键词： Fe-Ni alloys Electron beam physical vapor deposition (EBPVD) Nanostructured materials Hardness Thermal expansion Mossbauer spectroscopy

Optimization of Cu content for the development of high-performance T5-treated thixo-cast Al-7si-0.5Mg-Cu(wt.%)alloy

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Journal of Materials science & Technology 2021年第34期93卷 178-190页

作者： K.Yamamoto M.Takahashi Y.Kamikubo Y.sugiura s.Iwasawa T.Nakata s.Kamado Nagaoka University of Technology NagaokaJapan Asanuma Giken Co. Ltd.HamamatsuJapa Industrial Research Institute of shizuoka Prefecture ShizuokaJapan

Cu content has been successfully optimized in a thixo-cast and directly aged(T5-treatment)Al-7 si-0.5 Mg(wt.%)*** after the 0.5%Cu addition,plate-like Al_(2)Cu(θ’)phases,which contribute to high strengths and large plasticity,are *** formation of a large fraction of Cu-containing brittle phases could be suppressed as ***,the Al-7si-0.5Mg-0.5Cu alloy exhibits high ultimate tensile strength,0.2%proof stress,and elongation to failure of 296 MPa,209 MPa,and 8.8%,*** results in a high quality index similar to that of solution-treated and subsequently aged(T6-treated)Al-7 si-Mg alloys.A Cu addition over 1.0%further improves the strengths;however,this leads to poor ductility because of the high fraction of Cu-containing brittle phases.

关键词： Al-si-Mg-Cu alloy Thixo-casting T5-treatment Mechanical property Microstructure

structural phase transition, precursory electronic anomaly, and strong-coupling superconductivity in quasi-skutterudite (sr1-xCax)3Ir4sn13 and Ca3Rh4sn13

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Chinese Physics B 2018年第7期27卷 163-170页

作者： Jun Luo Jie Yang s Maeda Zheng Li Guo-Qing Zheng Institute of Physics Chinese Academy of Sciences and Beijing National Laboratory for Condensed Matter Physics Beijing 100190 China school of Physical sciences University of Chinese Academy of Sciences Beijing 100049 China Department of Physics Okayama University Okayama 700-8530 Japan

The interplay between superconductivity and structural phase transition has attracted enormous interest in recent years. For example, in Fe-pnictide high temperature superconductors, quantum fluctuations in association with structural phase transition have been proposed to lead to many novel physical properties and even the superconductivity itself. Here we report a finding that the quasi-skutterudite superconductors （sr1-xCax）3Ir4sn13 （x = 0, 0.5, 1） and Ca3Rh4snl3 show some unusual properties similar to the Fe-pnictides, through 119sn nuclear magnetic resonance （NMR） measurements. In （sr1-xCax）3Ir4sn13, the NMR linewidth increases below a temperature T＊ that is higher than the structural phase transition temperature ts. The spin-lattice relaxation rate （1/T1 ） divided by temperature （T）, 1/TI T and the Knight shift K increase with decreasing T down to T＊, but start to decrease below T＊, and followed by more distinct changes at ts. In contrast, none of the anomalies is observed in Ca3Rh4sn13 that does not undergo a structural phase transition. The precursory phenomenon above the structural phase transition resembles that occurring in Fe-pnictides. In the superconducting state of Ca3Ir4sn13, 1/T1 decays as exp（-△/kBT） with a large gap △ = 2.21kBTc, yet without a Hebel-slichter coherence peak, which indicates strong-coupling superconductivity. Our results provide new insight into the relationship between superconductivity and the electronic-structure change associated with structural phase transition.

关键词： nuclear magnetic resonance antiferromagnetic fluctuation structural phase transition phase diagram

Maximizing the visible light photoelectrochemical activity of B/N-doped anatase TiO_2 microspheres with exposed dominant {001} facets

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science China Materials 2018年第6期61卷 831-838页

作者： Xingxing Hong1 2 Yuyang Kang1 2 Chao Zhen1 Xiangdong Kang1 Li-Chang Yin1 John ts Irvine3 Lianzhou Wang4 Gang Liu1 2 Hui-Ming Cheng1 5 6 shenyang National Laboratory for Materials science Institute of Metal Research Chinese Academy of Sciences school of Materials science and Engineering University of Science and Technology of China school of Chemistry University of St. Andrews Nanomaterials Centre School of Chemical Engineering and AIBN the University of Queensland tsinghua-Berkeley shenzhen Institute Tsinghua University Center of Excellence in Environmental studies King Abdulaziz University

Anatase TiO2 microspheres with exposed dominant {001} facets were doped with interstitial boron to have a concentration gradient with the maximum concentration at the surface. They were then further doped with substitutional nitrogen by heating in an ammonia atmosphere at different temperatures from 440 to 560℃ to give surface N concentrations ranging from 7.03 to 15.47 at%. The optical absorption, atomic and electronic structures and visible-light photoelectrochemical water oxidation activity of these materials were investigated. The maximum activity of the doped TiO2 was achieved at a nitrogen doping temperature of 520℃ that gave a high absorbance over the whole visible light region but with no defect-related background absorption.

关键词： photoelectrochemistry red TiO2 water splitting doping

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新疆精河县蒙古族长调搜集整理研究概述

西部蒙古论坛 2020年第4期 81-95,M0005,M0006页

作者：策·巴图不详

The Mongolian ethaic gop in Jinghe County of Xinjiang has a long history and splendid traditional ***,collating and studying the Mongolian folk songs in Jinghe county are an important measure to im-plement General secretary Xi Jinpings important exposition on carrying forward the fine traditional Chinese *** this paper,the author collects the long tune folk songs of Jinghe County from various documents and publications,and makes an objective comment on *** author believes that as an autonomous region level intangible cultural heritage,the protection and inheritance of Jinghe County Mongolian long-tune folk songs is still in the basic stage of collection and *** should speed up the process of collection and collation,and should conduct a comprehensive study from various perspectives.

关键词： autonomous collection heritage

Thermo-kinetic characteristics on stabilizing hetero-phase interface of metal matrix composites by crystal plasticity finite element method

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Journal of Materials science & Technology 2024年第2期169卷 53-67页

作者： Y.B.Zhang s.J.song F.Liu state Key Laboratory of solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Analytical&Testing Center Northwestern Polytechnical UniversityXi’an 710072China

Using dislocation-based constitutive modeling in three-dimension crystal plasticity finite element(3D CPFE)simulations,co-deformation and instability of hetero-phase interface in different material systems were herein studied for polycrystalline metal matrix composites(MMCs).Local stress and strain fields in two types of 3layer MMCs such as fcc/fcc Cu-Ag and fcc/bcc Cu-Nb have been predicted under simple compressive ***,more severe strain-induced interface instability can be observed in the fcc/bcc systems than in the fcc/fcc systems upon refining to metallic nanolayered composites(MNCs).By detailed analysis of stress and strain localization,it has been demonstrated that the interface instability is always accompanied by high-stress concentration,i.e.,thermodynamic characteristics,or high strain prevention i.e.,kinetic characteristics,at the hetero-phase *** then follows that the thermodynamic driving forceG and the kinetic energy barrier Q during dislocation and shear banding can be adopted to classify the deformation modes,following the so-called thermo-kinetic *** by inserting a high density of high-energy interfaces into the Cu-Nb composites,such thermo-kinetic integration at the hetero-phase interface allows a successful establishment of MMCs with the high△G-high Q deformation mode,which ensures high hardening and uniform strain distri-bution,thus efficiently suppressing the shear band,stabilizing the hetero-phase interface,and obtaining an exceptional combination in strength and *** hetero-phase interface chosen by a couple of thermodynamics and kinetics can be defined as breaking the thermo-kinetic correlation and has been proposed for artificially designing MNCs.

关键词： Thermodynamics and kinetics Physics-based constitutive modeling Hetero-phase interface Crystal plasticity finite element

Adaptive Nonlinear sliding Mode Control for DC Power Distribution in Commercial Buildings

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Intelligent Automation & soft Computing 2023年第4期36卷 997-1012页

作者： R.Muthamil Arasi s.Padma Thiagarajar Polytechnic College SalemTamilnaduIndia sona College of Technology SalemTamilnaduIndia

The developing populace and industrialization power demand prompted the requirement for power generation from elective *** desire for this pursuit is solid due to the ever-present common assets of petroleum deri-vatives and their predominant ecological *** is generally acknowledged that sustainable power sources are one of the best answers for the energy *** these,Photovoltaic(PV)sources have many beneﬁts to bestow a very promising *** integrated into the existing power distribution infrastructure,the solar source will be more successful,requiring efﬁcient Direct Current(DC)-Alternating Current(AC)*** paper mainly aims to improve control-lers’performance between AC/DC Energy sources and the DC loads using the Adaptive Nonlinear sliding Mode(ANsM)control *** proposed ANsM method efﬁciently controls power quality issues,such as transient response,powerﬂow reliability and Total Harmonics Distortion(THD).The proposed con-troller is applied for both AC/DC and DC/DC converters and the performance of the proposed controller is validated through simulation checking the above *** simulation results conﬁrm ANsM conﬁguration is more reliable and efﬁcient than the existing fuzzy and sliding mode control methods.

关键词： Photovoltaic AC-DC converter DC-DC converter adaptive nonlinear sliding mode transient response total harmonics distortion

Effect of Element Distortion on the Numerical Dispersion of spectral Element Methods

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Communications in Computational Physics 2011年第4期9卷 937-958页

作者： s.P.Oliveira G.seriani Departamento de Matematica Universidade Federal do ParanaCuritiba-PR81531-980Brazil Istituto Nazionale di Oceanografia e di Geofisica sperimentale Borgo Grotta Gigante42/cSgonico(TS)34010Italy

spectral element methods are well established in the field of wave propagation,in particular because they inherit the flexibility of finite element methods and have low numerical dispersion *** latter is experimentally acknowledged,but has been theoretically shown only in limited cases,such as Cartesian *** is well known that a finite element mesh can contain distorted elements that generate numerical errors for very large *** the present work,we study the effect of element distortion on the numerical dispersion error and determine the distortion range in which an accurate solution is obtained for a given error *** also discuss a double-grid calculation of the spectral element matrices that preserves accuracy in deformed geometries.

关键词： spectral element method dispersion analysis slivering

Effect of Wetting-Drying Cycles on Redistribution of Lead in some semi-Arid Zone soils spiked with a Lead salt

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Pedosphere 2012年第3期22卷 304-313页

作者： H.KHODAVERDILOO M.RAHMANIAN s.REZAPOUR s.GHORBANI DAsHTAKI H.HADI F.X.HAN Department of soil science Urmia UniversityUrmia 57135-165 (Iran) Department of soil science Shahrekord UniversityShahrekord 88186/34141 (Iran) Department of Agronomy and Plant Breeding Urmia UniversityUrmia 57135-165 (Iran) Department of Chemistry and Biochemistry JacksonState UniversityJacksonMS 39217-0510 (USA)

Mobility and bioavailability of lead （Pb） could be affected considerably by soil physicochemical properties; however, less is known about the effect of Pb levels and aging time. This study was conducted to evaluate the effects of Pb levels and wetting-drying （WD） cycles on distribution and bioavailability of Pb in three semi-arid zone soils treated with different levels of Pb（NO3）2. Wetting-drying cycles simulated the actual field irrigation in the semi-arid soils. A soil with a long history of Pb contamination was also taken as a reference soil. The soils were spiked with various levels of Pb and incubated under WD cycles for 160 d. sequential extractions and batch sorption experiments were performed to assess the fractionation of Pb in the spiked soils. Redistribution index （Uts） and reduced partitioning parameter （IR） were applied to semi-quantify the distribution of Pb in the spiked soils. A small amount of Pb sorbed was desorbed by the soils, indicating a strong and irreversible binding of Pb in the studied soils. Contribution of carbonate-bound （Car） and residual （Res） Pb fl＇actions to the total Pb of the soils was more than 97%. The Car, soluble plus exchangeable （sE）, and organic matter-bound （OMB） fractions of Pb were transferred to the Res fraction under the WD cycles. The IR and Uts values were influenced by Pb loading levels and WD; therefore, the Pb lability and/or redistribution pattern could semi-quantitatively be assessed via these parameters. At the end of the experiment, the Ia and Uts values for the Pb salt-spiked soils did not show the quasi- equilibrium state. The lability of Pb in the soils decreased with increasing incubation time and showed a strong dependence on Pb levels and soil chemical composition. WD cycles significantly affected the overall lability of Pb in soils through influencing the redistribution of Pb among solid-phase components.

关键词： bioavailability heavy metals mobility redistribution index reduced partitioning parameter