On Specific Phase Transitions to the Compound-Like Impurity Nanosegregation Structures at Dislocations and Grain Boundaries in Metals and their Influence on Diffusion-Assisted Processes

2008 ◽  
pp. 91-118
Author(s):  
Yury S. Nechaev
Keyword(s):  
Phase Transitions ◽  
Grain Boundaries ◽  
Specific Phase Transitions ◽  
Specific Phase

On Specific Phase Transitions to the Compound-Like Impurity Nanosegregation Structures at Dislocations and Grain Boundaries in Metals and their Influence on Diffusion-Assisted Processes

2008 ◽  
Vol 138 ◽  
pp. 91-118 ◽  
Author(s):  
Yuriy S. Nechaev
Keyword(s):  
Phase Transitions ◽  
Grain Boundaries ◽  
Elevated Temperatures ◽  
Physical And Mechanical Properties ◽  
Nanostructured Metals ◽  
Study Results ◽  
And Diffusion ◽  
Specific Phase Transitions ◽  
Specific Phase

Specific phase transitions to the compound-like impurity nanosegregation structures at dislocations and grain boundaries in metals and their influence on diffusion-assisted processes are considered, mainly, on the basis of the thermodynamic analysis of the related experimental data. The following systems and aspects are in detail considered: (1) the hydride-like nanosegregation of hydrogen at dislocations and grain boundaries in palladium and their influence on the apparent characteristics of hydrogen solubility and diffusivity in palladium; (2) the physics of the anomalous characteristics of diffusion of Fe and other transition impurities in crystalline Al at elevated temperatures, the role of the compound-like nanosegregation (CLNS) of Fe and the others at dislocations and grain boundaries in Al, analysis of the Mössbauer and diffusion data on CLNS of Fe at grain boundaries and dislocations in Al; (3) some new physical aspects of internal oxidation and nitridation of metals (for Cu-0.3%Fe alloy/Cu2O surface layer, and for (Ni-5%Cr) alloy / N2 gas), the role of the compound-like impurity nanosegregation at dislocations and grain boundaries, study results on the deviations from the classical theories predictions and their interpretation. The possibility is considered of nanotechnology applications of the study results for creation of nanostructured metals with compound-like nanosegregation structures at grain boundaries, in order to obtain specific physical and mechanical properties of such a cellural-type nanocomposites. In particular, it can be complex hydride-like, carbide-like, nitride-like, carbide-nitride-like, oxide-like or intermetallide-like nanosegregation structures at grain boundaries of nanostructured metals.

scholarly journals Refining the Design of Diblock Elastin-Like Polypeptides for Self-Assembly into Nanoparticles

Polymers ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1470
Author(s):  
Michèle Dai ◽  
Evangelos Georgilis ◽  
Guillaume Goudounet ◽  
Bertrand Garbay ◽  
Jan Pille ◽  
...  
Keyword(s):  
Phase Transition ◽  
Phase Transitions ◽  
Self Assembly ◽  
Diblock Copolymers ◽  
Thermal Phase Transition ◽  
Thermal Phase ◽  
Specific Phase Transitions ◽  
Specific Phase

Diblock copolymers based-on elastin-like polypeptide (ELP) have the potential to undergo specific phase transitions when thermally stimulated. This ability is especially suitable to form carriers, micellar structures for instance, for delivering active cargo molecules. Here, we report the design and study of an ELP diblock library based on ELP-[M1V3-i]-[I-j]. First, ELP-[M1V3-i]-[I-j] (i = 20, 40, 60; j = 20, 90) that showed a similar self-assembly propensity (unimer-to-aggregate transition) as their related monoblocks ELP-[M1V3-i] and ELP-[I-j]. By selectively oxidizing methionines of ELP-[M1V3-i] within the different diblocks structures, we have been able to access a thermal phase transition with three distinct regimes (unimers, micelles, aggregates) characteristic of well-defined ELP diblocks.

scholarly journals SATB1 undergoes isoform-specific phase transitions in T cells

2021 ◽  
Author(s):  
Tomas Zelenka ◽  
Petros Tzerpos ◽  
Giorgos Panagopoulos ◽  
Konstantinos Tsolis ◽  
Dionysios-Alexandros Papamatheakis ◽  
...  
Keyword(s):  
Phase Transitions ◽  
Gene Expression Regulation ◽  
Nuclear Bodies ◽  
Intracellular Space ◽  
Post Translational Modifications ◽  
Cellular Processes ◽  
Nuclear Rna ◽  
Separation Phase ◽  
Specific Phase Transitions ◽  
Specific Phase

Intracellular space is demarcated into functional membraneless organelles and nuclear bodies via the process of phase separation. Phase transitions are involved in many functions linked to such bodies as well as in gene expression regulation and other cellular processes. In this work we describe how the genome organizer SATB1 utilizes its prion-like domains to undergo phase transitions. We have identified two SATB1 isoforms with distinct biophysical behavior and showed how phosphorylation and interaction with nuclear RNA, impact their phase transitions. Moreover, we show that SATB1 is associated with transcription and splicing, both of which evinced deregulation in Satb1 knockout mice. Thus, the tight regulation of different SATB1 isoforms levels and their post-translational modifications are imperative for SATB1's physiological roles in T cell development while their deregulation may be linked to disorders such as cancer.

GRAIN BOUNDARIES: PHASE TRANSITIONS AND CRITICAL PHENOMENA

1991 ◽  
Vol 05 (19) ◽  
pp. 2989-3028 ◽  
Author(s):  
E.I. RABKIN ◽  
L.S. SHVINDLERMAN ◽  
B.B. STRAUMAL
Keyword(s):  
Phase Transitions ◽  
Grain Boundary ◽  
Grain Boundaries ◽  
Critical Phenomena ◽  
External Surface ◽  
Theoretical Models ◽  
Boundary Structure ◽  
Boundary Phase ◽  
Recent Experimental Data ◽  
Grain Boundary Structure

Recent theories of grain boundary structure have been reviewed briefly. The possibility of existence of the same variety of phase transitions on grain boundaries as that on the crystal external surface has been demonstrated. Recent experimental data and theoretical models concerning grain boundary phase transitions are critically analysed. Grain boundary phase transitions connected with the formation of thin disordered layers on the boundary (prewetting, premelting) are particularly distinguished. Results of recent indirect experiments, which may be treated in terms of prewetting and premelting, have been reviewed. Experimentally observed critical phenomena in the vicinity of the prewetting transition on the tin-germanium interphase boundary have been discussed in terms of the critical exponents theory. Some ideas regarding directions of further research are presented.

Pseudopartial Grain Boundary Wetting: Key to the Thin Intergranular Layers

2013 ◽  
Vol 333 ◽  
pp. 175-192 ◽  
Author(s):  
Boris B. Straumal ◽  
Alexey Rodin ◽  
A.E. Shotanov ◽  
Alexander B. Straumal ◽  
Olga A. Kogtenkova ◽  
...  
Keyword(s):  
Contact Angle ◽  
Phase Transitions ◽  
Grain Boundary ◽  
Grain Boundaries ◽  
Thin Layers ◽  
Second Phase ◽  
Triple Junctions ◽  
Complete Wetting ◽  
Grain Boundary Wetting

The thin layers of a second phase (also called complexions) in grain boundaries (GB) and triple junctions (TJs) are more and more frequently observed in polycrystals. The prewetting (or premelting) phase transitions were the first phenomena proposed to explain their existence. The deficit of the wetting phase in case of complete wetting can also lead to the formation of thin GB and TJ phases. However, only the phenomenon of pseudopartial (or pseudoincomplete, or constrained complete) wetting permitted to explain, how the thin GB film can exist in the equilibrium with GB lenses of a second phase with non-zero contact angle.

Sign in / Sign up

Export Citation Format

Share Document