General model for the kinetics of solute diffusion at solid-solid interfaces

The most-known model of sleep-wake regulation includes different formulae describing the kinetics of three separate processes, i.e., homeostatic, circadian, and ultradian. We tried to explain all these processes within a more parsimonious modeling framework and to use the EEG recordings of baseline night sleep for derivation of the model’s parameters and for prediction of the effects of experimental manipulations with sleep-wake regimen.

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Liquid phase stratification induced by large temperature gradient during spinodal decomposition in Fe–Cr alloys: A phase-field study

Modern Physics Letters B ◽

10.1142/s0217984921503747 ◽

2021 ◽

pp. 2150374

Author(s):

Lifei Du ◽

Runbo Tian ◽

Tiantian Shi ◽

Youqi Cao

Keyword(s):

Liquid Phase ◽

Temperature Gradient ◽

Spinodal Decomposition ◽

Phase Field ◽

Anisotropic Diffusion ◽

Phase Field Model ◽

Solute Diffusion ◽

Large Temperature ◽

Cahn Hilliard Equation ◽

Kinetics Of

The spinodal decomposition in Fe-40at.%Cr binary alloy is numerically studied by implementing the phase-field model based on Cahn–Hilliard equation. Effects of different temperature gradients on the solute distributing characteristics during the spinodal decomposition are investigated. In the system with a temperature gradient, the phase decomposition happens gradually from low temperature to high temperature, and a metastable stratification is achieved with specified temperature distribution. The critical temperature and corresponding temperature gradient are specified for the obvious solute stratification in the binary Fe–Cr alloy. The kinetics of the solute diffusion during the spinodal decomposition is discussed to reveal the liquid phase stratification induced by the anisotropic diffusion with the nonuniform temperature field. Therefore, tailoring the heat treatment during the spinodal decomposition in Fe–Cr binary alloys might be an efficient way to obtain nanometer coherent microstructures with specified solute distribution.

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The sequence of events during folding of a DNA origami

Science Advances ◽

10.1126/sciadv.aaw1412 ◽

2019 ◽

Vol 5 (5) ◽

pp. eaaw1412 ◽

Cited By ~ 10

Author(s):

Fabian Schneider ◽

Natalie Möritz ◽

Hendrik Dietz

Keyword(s):

General Model ◽

Dna Origami ◽

Folding Kinetics ◽

Reference Dataset ◽

Time Data ◽

Sequence Of Events ◽

Fine Detail ◽

Real Time Data ◽

Kinetics Of ◽

Comprehensive Reference

We provide a comprehensive reference dataset of the kinetics of a multilayer DNA origami folding. To this end, we measured the folding kinetics of every staple strand and its two terminal segments during constant-temperature assembly of a multilayer DNA origami object. Our data illuminate the processes occurring during folding of the DNA origami in fine detail, starting with the first nucleating double-helical domains and ending with the fully folded DNA origami object. We found a complex sequence of folding events that cannot be explained with simplistic local design analysis. Our real-time data, although derived from one specific DNA origami object, through its sheer massive detail, could provide the crucial input needed to construct and test a quantitatively predictive, general model of DNA origami assembly.

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Self-Diffusion, Solute-Diffusion and Interdiffusion in Binary Intermetallics

Diffusion Foundations ◽

10.4028/www.scientific.net/df.2.1 ◽

2014 ◽

Vol 2 ◽

pp. 1-72 ◽

Cited By ~ 6

Author(s):

Helmut Mehrer

Keyword(s):

Boundary Diffusion ◽

Functional Materials ◽

Tracer Diffusion ◽

Solute Diffusion ◽

Diffusion Couples ◽

Self Diffusion ◽

Solid Diffusion ◽

State Diffusion ◽

Iron Nickel ◽

Kinetics Of

800x600 Intermetallics are compounds of two metals or of metal(s) and semimetal(s). Their structures are usually different from those of the constituents. Some intermetallics are interesting functional materials, others have attracted attention as high-temperature structural materials. We remind the reader of some fundamentals of solid-state diffusion and to the major techniques for tracer diffusion measurements, interdiffusion studies and the growth kinetics of layers in solid diffusion couples. Starting from self-diffusion, which is the most basic diffusion phenomenon in any solid, the paper covers the main features of diffusion in binary intermetallics from the systems Cu-Zn, Ni-Al, Fe-Al, Mg-Al, Ni-Ge, Ni-Ga, Fe-Si, Ti-Al, Ni-Mn, Mo-Si, Co-Nb and Ni-Nb.. We illustrate the influence of phase transitions on diffusion and point out some common features of diffusion in intermetallics. We discuss in detail diffusion in silicides of iron, molybdenum and of silicides of refractory metals. We also consider aluminides of iron, nickel, and titanium and in the aluminium-magnesium system. We consider diffusion in intermetallics of the cobalt-niobium and nickel-niobium system and in in the Nb-Sn and V-Ga systems. We finish with some remarks about grain boundary diffusion in intermetallics. Normal 0 21 false false false UK X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Calibri","sans-serif";}

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A General Model for the Kinetics of Self-Condensing Vinyl Polymerization

Macromolecules ◽

10.1021/ma800209q ◽

2008 ◽

Vol 41 (12) ◽

pp. 4429-4434 ◽

Cited By ~ 28

Author(s):

Zhiping Zhou ◽

Deyue Yan

Keyword(s):

General Model ◽

Vinyl Polymerization ◽

Kinetics Of

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Kinetics of Guided Growth of Horizontal GaN Nanowires on Flat and Faceted Sapphire Surfaces

Nanomaterials ◽

10.3390/nano11030624 ◽

2021 ◽

Vol 11 (3) ◽

pp. 624

Author(s):

Amnon Rothman ◽

Jaroslav Maniš ◽

Vladimir G. Dubrovskii ◽

Tomáš Šikola ◽

Jindřich Mach ◽

...

Keyword(s):

Physical Properties ◽

Growth Mechanism ◽

Growth Kinetics ◽

General Model ◽

Rational Approach ◽

Thomson Effect ◽

Guided Growth ◽

Gan Nanowires ◽

Kinetics Of ◽

Structure Orientation

The bottom-up assembly of nanowires facilitates the control of their dimensions, structure, orientation and physical properties. Surface-guided growth of planar nanowires has been shown to enable their assembly and alignment on substrates during growth, thus eliminating the need for additional post-growth processes. However, accurate control and understanding of the growth of the planar nanowires were achieved only recently, and only for ZnSe and ZnS nanowires. Here, we study the growth kinetics of surface-guided planar GaN nanowires on flat and faceted sapphire surfaces, based on the previous growth model. The data are fully consistent with the same model, presenting two limiting regimes—either the Gibbs–Thomson effect controlling the growth of the thinner nanowires or surface diffusion controlling the growth of thicker ones. The results are qualitatively compared with other semiconductors surface-guided planar nanowires materials, demonstrating the generality of the growth mechanism. The rational approach enabled by this general model provides better control of the nanowire (NW) dimensions and expands the range of materials systems and possible application of NW-based devices in nanotechnology.

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