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Effect of Solute Contents of Al-Ni-Sr Alloy on Glass Forming Ability and Thermal Stability

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journal of Rare Earths 2004年第Z2期22卷 73-77页

作者： Taek Soo Kim j K Lee H j Kim j C Bae Advanced Materials R&D Center Korea Institute of Industrial Technology994-32 Dongchun-dongYeonsu-kuIncheon 406-130Korea Advanced Materials R&D CenterKorea Institute of Industrial Technology994-32 Dongchun-dongYeonsu-kuIncheon 406-130Korea Advanced Materials R&D CenterKorea Institute of Industrial Technology994-32 Dongchun-dongYeonsu-kuIncheon 406-130Korea Advanced Materials R&D CenterKorea Institute of Industrial Technology994-32 Dongchun-dongYeonsu-kuIncheon 406-130Korea

Glass forming ability (GFA) and structural characterization of a new amorphous Al-Ni-Sr alloy melt spun were investigated on the theory of the factors for the glass formation. The GFA was varied with the ratio of Ni to Sr in detail and successful amorphous phase dispersed with 2 ～ 5 nm precipitates was prepared from Al-Ni5-Sr3. Thermal stability and crystallization behavior of the amorphous phase were determined by continuous and isothermal heating technique on DCS, resulting that the crystallization occurs by the growth of fcc Al nanocrystals on the preexistent nuclei.

关键词： glass formation crystallization Al base amorphous alloys rapid solidification

Mg-Al Alloys Manufactured by Casting and Hot Working Process

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journal of Materials Science & Technology 2008年第1期24卷 96-98页

作者： j.M.Kim j.H.jun W.j.jung Department of Applied Materials Eng. Hanbat National University Daejeon 305-719 Korea Light Materials Team Korea Institute of Industrial Technology Incheon 406-800 Korea

Mechanical properties of Mg-Al based alloys at different fabrication state,namely as-cast,hot rolled,and annealed,were investigated to develop the alloys that are suitable for the casting/hot working ***- imental results indicated that the castability such as hot cracking resistance tends to improve with increasing the aluminum ***,the elongation at elevated temperatures was observed to decrease as the AI content increases,implying difficulties in hot forming.A small amount of Zr additions could significantly enhance the room temperature mechanical properties of hot-rolled Mg-6%Al-1%Zn *** tendency of remarkable grain coarsening at high temperatures was effectively reduced by the Zr *** analyses suggested that very fine Al-3Zr precipitates formed in the Zr-added alloy are responsible for the obtained results.

关键词： Magnesium Casting Forming Tensile properties

Studying turbulence structure near the wall in hydrodynamic flows:An approach based on the Schur decomposition of the velocity gradient tensor

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journal of Hydrodynamics 2022年第5期34卷 806-825页

作者： Christopher j.Keylock School of Architecture Building and Civil EngineeringLoughborough UniversityLeicestershireUK

The Schur decomposition of the velocity gradient tensor(VGT)is an alternative to the classical Cauchy-Stokes decomposition into rotation rate and strain rate ***,there have been several strands of work that have employed this decomposition to examine the physics of turbulence dynamics,including approaches that combine the Schur and Cauchy-Stokes *** are briefly reviewed before the latter approach is set *** partitions the rotation rate and strain rate tensors into normal/local and non-normal/non-local *** then study the relation between the VGT dynamics and ejection-sweep events in a channel flow *** show that the sweeps in particular exhibit novel behaviour compared with either the other quadrants,or the flow in general,with a much-reduced contribution to the dynamics from the non-normal terms above the viscous *** particular,the reduction in the production term that is the interaction between the non-normality and the normal straining reduces in the log-layer as a consequence of an absence of alignment between the non-normal vorticity and the strain rate *** have been early forays into using the Schur transform approach for subgrid-scale modelling in large-eddy simulation(LES)and this would appear to be an exciting way forward.

关键词： Turbulence channel flow velocity gradient tensor Schur decomposition

Natural products and drug discovery

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National Science Review 2022年第11期9卷 37-57页

作者： David j.Newman NIH Special Volunteer

This review covers the recent history of a series of very important natural products and their derivatives that are currently in use or under evaluation in the areas of anti-infectives, important cancer treatments that include antibody drug conjugates, followed by a discussion of type 2 diabetes(T2DM) drugs and angiotensin converting enzyme inhibitors. The current structures of the agents are shown, though in the case of some peptides used in T2DM drugs the standard single leTher abbreviation for an amino acid is used.

关键词： artemisinin glycopeptides anthracyclines dolastatin diabetes 2 ACE inhibitors

Exploring the concept of castability in magnesium die-casting alloys

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journal of Magnesium and Alloys 2021年第1期9卷 102-111页

作者： j.P.Weiler Meridian Lightweight Technologies Canada

This paper provides a summary of the recent work completed and history of the measure of manufacturability in the magnesium diecasting *** most popular die-casting alloys utilized in this industry are based on the Mg-Al system,including AZ91,AM60 and *** are well-established alloys,and are generally considered to be highly ***,the concept of castability in magnesium die-casting is not a well-defined characteristic or quantitative material *** a result,the author investigates the subject of castability for magnesium die-cast alloys and how it relates to the development of alloys for innovative applications or improved *** paper provides a summary of some key findings in literature on the castability of magnesium die-cast alloys,how castability is defined and evaluated,the impact of different alloying elements on the castability of magnesium alloys,and suggestions for future work.©2020 Published by Elsevier *** behalf of Chongqing University.

关键词： casting alloys property.

Exploring effects of property variation on fragmentation of metal rings using a simple model

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Defence Technology（防务技术） 2023年第5期23卷 1-7页

作者： j.D.Robson Department of Materials The University of ManchesterManchesterM139PLUK

A simple finite element implementation of the Mott model for fragmentation of a thin walled ring has been implemented and used to explore the effect of local variations in fracture strain around the *** model has successfully reproduced the fragment size distributions previously reported,which follow a characteristic“Mott distribution”form,providing sufficient(1000)simulations are *** has been shown that this form is retained even when there are large differences in the random distribution of fracture strains or a different choice of function used to describe the fracture strain *** these cases,the strain rate has a much stronger effect than fracture strain distribution the on the average fragment size and fragment ***,for cases where there are a small number of local defects that strongly reduce the fracture strain at certain locations around the ring,the predicted fragment size distribution develops a bimodal *** is also the case for large but gradual variations in fracture strain with position around the *** results have implications for cases where a small number of large pre-existing defects exist,or processing has led to macrozones in the *** utility of a simple fast running model to study these cases is discussed.

关键词： Fragmentation Mott model Property variation

Segmentations of foreland belts and their tectonic mechanism in the Southwest Tarim Basin

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Science China Earth Sciences 2005年第10期48卷 1585-1598页

作者： j. Canerot j. Deramond Lab. de Bassin Dynamique Sedimentaire Universite Paul Sabatier Toulouse III 39 Allee Jules-Guesde 31062 Toulouse FranceLab. de Bassin Dynamique Sedimentaire Universite Paul Sabatier Toulouse III 39 Allee Jules-Guesde 31062 Toulouse France

Based on lots of field investigations and comprehensive interpretations of seismic profiles with outcrop cross-sections, this paper shows that the foreland belts surrounding the Southwest Tarim Foreland Basin have the regularity of segmentation along the strike of foreland belts. There are many thin-skinned thrusting systems thrusting from mountains to the basin and the arcuate back-thrusting systems to the mountains distributed at intervals in the front of West Kunlun-Pamir and Southern Tianshan. Between thrusting and back-thrusting systems, the strike-slip faults developed. The northeast uplifts and depressions of Southwest Tarim Basin correspond with the segmentation of foreland basin. The thin-skinned thrusting system is formed in the case that the thickness of sedimentary covers is less than 10 km in depth where the basement is an uplift belt in general. The back-thrusting systems and triangle zones are formed in the case that the thickness of sedimentary covers is larger than 8 km in depth where the basement is a depression zone. The main mechanics of segmentation of foreland basin are the difference of mountain uplift and deformation rate along the longitude of the mountains, the huge sedimentary rocks in different depression centers, the uplift belts and depression zones in the basement rocks, and multi-displaced weak layers in the foreland basin. The segmentation of Southwest Tarim Foreland Basin is due to the intra-plate deformation of re-orogenies of West Kunlun-Pamir and Southwest Tianshan and the co-related deformation between mountains and basement of basin since Neocene.

关键词： Southwest Tarim Basin, foreland basin,West Kunlun-Pamir and Tianshan, tectonic segmentation,structure of basement.

Faraday rotations,ellipticity,and circular dichroism in magneto-optical spectrum of moire superlattices

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Chinese Physics B 2021年第7期30卷 18-32页

作者： j A Crosse Pilkyung Moon Arts and Sciences New York University ShanghaiShanghai 200122China NYU-ECNU Institute of Physics at NYU Shanghai Shanghai 200062China Department of Physics New York UniversityNew York 10003USA

We study the magneto-optical conductivity of a number of van der Waals heterostructures,namely,twisted bilayer graphene,AB–AB and AB–BA stacked twisted double bilayer graphene and monolayer graphene and AB-stacked bilayer graphene on hexagonal boron *** the magnetic field increases,the absorption spectrum exhibits a self-similar recursive pattern reflecting the fractal nature of the energy *** twisted bilayer graphene displays only weak circular dichroism,the other four structures display strong circular dichroism with monolayer graphene and AB-stacked bilayer graphene on hexagonal boron nitride being particularly pronounced owing to strong inversion symmetry breaking properties of the hexagonal boron nitride *** the left and right circularly polarized light interact with these structures differently,plane-polarized incident light undergoes a Faraday rotation and gains an ellipticity when *** size of the respective angles is on the order of a degree.

关键词： 2D-materials van der Waals heterostructures magneto-optical conductivity graphene

Creating and moving nanoantenna cold spots anywhere

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Light(Science & Applications) 2022年第10期11卷 2335-2344页

作者： Alex j.Vernon Francisco j.Rodriguez-Fortuno Department of Physics King's College LondonStrandLondon WC2R 2LSUnited Kingdom

Cold spots are sub-wavelength regions which might emerge near a nanoantenna,should one or more components of some far-field illumination cancel out with scattered *** show that by changing only the polarisation,amplitude,and phase of two plane waves,a unique,zero-magnitude and highly sub-wavelength cold spot can be created and moved anywhere in the space around a nanoantenna of any arbitrary *** can be achieved using ultra-fast modulated pulses,or a time-harmonic *** disturbed by a change in the nanoantenna's material or position,a manufactured cold spot is fragile and could be used in nanoscale *** technique exploits the linearity of Maxwell's equations and could be adapted to manipulate any phenomena governed by the linear wave equation,including acoustic *** is a means for potentially ultra-fast sub-wavelength electric field manipulation.

关键词： illumination scattered arbitrary