scholarly journals Internal melt figures in ice by rapid adiabatic compression

1994 ◽  
Vol 40 (134) ◽  
pp. 132-134
Author(s):  
R.E. Gagnon ◽  
C. Tulk ◽  
H. Kiefte
Keyword(s):  
Phase Transformations ◽  
Grain Boundaries ◽  
Single Crystals ◽  
Adiabatic Compression ◽  
Air Bubbles ◽  
Water Ice ◽  
Deep Focus ◽  
And Behavior ◽  
First Time

AbstractSingle crystals and bicrystals of water ice have been adiabatically pressurized to produce, and clearly illustrate, two types of internal melt figures: (1) dendritic figures that grow from nucleation imperfections on the specimen’s surface, or from air bubbles at grain boundaries, into the ice as pressure is elevated; and (2) compression melt fractures, flat liquid-filled disks, that nucleate at imperfections in the crystal and grow with the application of pressure eventually to sprout dendritic fingers at the periphery. The transparency of the ice permitted visualization of the growth and behavior of the figures, and this could be an important tool in understanding the role of phase transformations in deep-focus earthquakes. Correlation between figure size and pressure is noted for the first time.

Internal melt figures in ice by rapid adiabatic compression

1994 ◽  
Vol 40 (134) ◽  
pp. 132-134 ◽  
Author(s):  
R.E. Gagnon ◽  
C. Tulk ◽  
H. Kiefte
Keyword(s):  
Phase Transformations ◽  
Grain Boundaries ◽  
Single Crystals ◽  
Adiabatic Compression ◽  
Air Bubbles ◽  
Water Ice ◽  
Deep Focus ◽  
And Behavior ◽  
First Time

Abstract Single crystals and bicrystals of water ice have been adiabatically pressurized to produce, and clearly illustrate, two types of internal melt figures: (1) dendritic figures that grow from nucleation imperfections on the specimen’s surface, or from air bubbles at grain boundaries, into the ice as pressure is elevated; and (2) compression melt fractures, flat liquid-filled disks, that nucleate at imperfections in the crystal and grow with the application of pressure eventually to sprout dendritic fingers at the periphery. The transparency of the ice permitted visualization of the growth and behavior of the figures, and this could be an important tool in understanding the role of phase transformations in deep-focus earthquakes. Correlation between figure size and pressure is noted for the first time.

The role of pathos: from argumentative responses to feeling and emotions

2017 ◽  
Author(s):  
Michel Meyer
Keyword(s):  
Short Distance ◽  
Social World ◽  
Legal Rhetoric ◽  
Law And Politics ◽  
The Social ◽  
And Behavior ◽  
First Time

Chapter 10 is devoted to the role of emotions or pathos. Pathos was the term ordinarily used to denote the notion of audience. For the first time since Aristotle, emotions receive a full role in a treatise on rhetoric. The responses of the audience are modulated by its emotions. What is their nature and how precisely do they operate? The areas of political and legal rhetoric are examined here in the light of an original view of the theory of distance: values at greater distance become passions at short distance, and this is one of the features which demarcates politics from law. Law and politics are not merely argumentative, nor are they entirely emotional. The norms they codify are often implicit in their shaping of our mutual expectations and behavior in the social world.

Digesting the emerging role for the gut microbiome in central nervous system demyelination

2014 ◽  
Vol 20 (12) ◽  
pp. 1553-1559 ◽  
Author(s):  
Jennifer Joscelyn ◽  
Lloyd H Kasper
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Gut Microbiome ◽  
Host Immunity ◽  
Future Research ◽  
Environmental Risk Factor ◽  
Central Nervous System Demyelination ◽  
And Behavior ◽  
First Time

The fields of microbiology, immunology, neurology and nutrition are rapidly converging, as advanced sequencing and genomics-based methodologies have enabled the mapping out of the microbial diversity of humans for the first time. Bugs, guts, brains and behavior were once believed to be separate domains of clinical practice and research; however, recent observations in our understanding of the microbiome indicate that the boundaries between domains are becoming permeable. This permeability is multidirectional: Biological systems are operating simultaneously in a vastly complex and interconnected web. Understanding the microbiome-gut-brain axis will entail fleshing out the mechanisms by which transduction across each domain occurs, allowing us ultimately to appreciate the role of commensal organisms in shaping and modulating host immunity. This article will highlight animal and human research to date, as well as highlight directions for future research. We speculate that the gut microbiome is potentially the premier environmental risk factor mediating inflammatory central nervous system demyelination, in particular multiple sclerosis.

Electron Microscopy Observations on the Role of Twinning in the Evolution of Microstructures

2002 ◽  
Vol 8 (4) ◽  
pp. 247-256 ◽  
Author(s):  
U. Dahmen ◽  
C.J.D. Hetherington ◽  
V. Radmilovic ◽  
E. Johnson ◽  
S.Q. Xiao ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Phase Transformations ◽  
Grain Boundaries ◽  
Microstructural Evolution ◽  
Equilibrium Shape ◽  
High Resolution Electron Microscopy ◽  
Resolution Electron ◽  
Multiple Twinning

Twinning plays an important role in phase transformations and can have significant effects on microstructural evolution. Different roles of twinning in the development of microstructures during precipitation and phase transformations are reviewed and illustrated with examples from investigations by high-resolution electron microscopy, including the effect of multiple twinning on the development of Ge precipitates in Al-Ge and Ag-Ge alloys, the twin dissociation of grain boundaries in Au, the formation of hexagonal Si at twin intersections and the effect of twin boundaries on the equilibrium shape of Pb inclusions in Al.

The Role of Grain Boundaries and other Defects on Phase Transformations Induced by Severe Plastic Deformation

2015 ◽  
Vol 5 ◽  
pp. 77-92 ◽  
Author(s):  
Xavier Sauvage ◽  
Yana Nasedkina
Keyword(s):  
Plastic Deformation ◽  
Severe Plastic Deformation ◽  
Phase Transformations ◽  
Grain Boundaries ◽  
Mechanical Mixing ◽  
Ultrafine Grained ◽  
Ultrafine Grained Materials ◽  
Underlying Mechanisms ◽  
Scientific Questions

During the past two decades, processing of ultrafine grained materials using severe plastic deformation techniques has attracted great interest in the scientific community. Although the up-scaling of processes and the lack of ductility of ultrafine grained alloys are still some important challenges, these techniques look promising because they produce bulk materials free of porosities. More recently, some strategies to combine precipitation hardening and ultrafine grained structures have been proposed. It has also been shown that nanoscaled composite materials could be successfully processed. This experimental work rose however some very fundamental scientific questions about the influence of severe plastic deformation on the precipitation mechanisms or on the formation of supersaturated solid solution through mechanical mixing. The driving force and the thermodynamics of these phase transformations are of course affected by the high amount of energy stored in severely deformed alloys, especially as interfacial energy. But grain boundaries, with the help of dislocations and point defects, also play an important role in the kinetics. In this paper, it is proposed to shortly review these phenomena and the underlying mechanisms with a special emphasis on the contribution of grain boundaries.

Floating zone growth and optical phonon behavior of corundum Mg4Ta2O9 single crystals

RSC Advances ◽  
2015 ◽  
Vol 5 (82) ◽  
pp. 66988-66993 ◽  
Author(s):  
Liang Li ◽  
Wenqiang Liu ◽  
Bo Han ◽  
Xilian Jin ◽  
Fangfei Li ◽  
...  
Keyword(s):  
Grain Boundaries ◽  
Single Crystals ◽  
Optical Phonon ◽  
Infrared Heating ◽  
Floating Zone ◽  
Zone Method ◽  
Floating Zone Method ◽  
First Time ◽  
Zone Growth

We demonstrate that corundum Mg4Ta2O9 crystals, free of low-angle grain boundaries and bubbles, were prepared for the first time by the infrared heating optical floating zone method.

A kinetic study of the phase transformations in Al2O3 and Na2O · 6Al2O3 by a combined use of 27Al MAS NMR spectroscopy and x-ray diffraction: Importance of nucleation

1991 ◽  
Vol 6 (12) ◽  
pp. 2701-2705 ◽  
Author(s):  
S. Prabakar ◽  
K.J. Rao ◽  
C.N.R. Rao
Keyword(s):  
Nmr Spectroscopy ◽  
Phase Transformations ◽  
Mas Nmr ◽  
X Ray Diffraction ◽  
X Ray ◽  
Combined Use ◽  
27Al Mas Nmr ◽  
First Time ◽  
Kinetics Of

Phase transformations of Al2O3 and Na2O · 6Al2O3 prepared by the gel route have been investigated for the first time by 27Al MAS NMR spectroscopy in combination with x-ray diffraction. Of particular interest in the study is the kinetics of the γ → α and γ → β transformations, respectively, in these two systems. Analysis of the kinetic data shows the important role of nucleation in both these transformations.

scholarly journals Compositional content of English musical and rock opera texts: linguistic aspect

XLinguae ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 52-59
Author(s):  
Venera Alpysbayeva ◽  
Togzhan Ospanova ◽  
Beishenaliev Almazbek ◽  
Tony Dimitrova Shekerdzhieva-Novak ◽  
Begalinova Gulnar
Keyword(s):  
Active Member ◽  
Poetic Discourse ◽  
Speech Interaction ◽  
Cognitive Activities ◽  
The Individual ◽  
Linguistic Aspect ◽  
And Behavior ◽  
First Time ◽  
Rock Opera

Every day, every active member of society deals with various types of media, interacts with other people, is engaged in cognitive activities while falling under the influence of external factors that influence a person’s consciousness, thinking, and behavior. All these processes take place in a communication situation, in which the individual inevitably becomes a participant when interacting with the outside world. One of the goals of research in the field of communicative linguistics is to identify and formulate criteria for ensuring the success (consistency) of speech interaction. Our research is devoted to the study of the linguistic problem of the text, which is proposed to be considered on the example of a musical and rock opera text as an element of a particular communicative phenomenon - musical and poetic discourse. The relevance of the work is based on the importance of the role of the linguistic component in the process of creating and perceiving the lyrics of a number of modern musical styles, which are currently one of the actively used tools for conveying information to the mass audience and influencing both the communicative activity of an everyday person and his worldview. The scientific novelty of this research lies in the fact that for the first time, it analyzes a previously unexplored linguistic phenomenon - the linguistic, musical, and rock opera texts. The uniqueness of the study lies in the fact that the theoretical and practical aspects of the functioning of texts are analyzed, the previously existing interpretations of this concept are systematically considered and based on our interpretation of this term, for the first time, an analysis is carried out concerning the corresponding type of discourse

Elucidation of block boundaries as the dissolution channels in hydrated cement

1978 ◽  
Vol 36 (1) ◽  
pp. 484-485
Author(s):  
N.V. Belov ◽  
U.I. Papiashwili ◽  
B.E. Yudovich
Keyword(s):  
Liquid Phase ◽  
Grain Boundaries ◽  
Benzoyl Peroxide ◽  
Phase Contrast ◽  
Active Role ◽  
Point Of View ◽  
Hardened Cement ◽  
Hydrated Cement ◽  
Hardened Cement Paste

It has been almost universally adopted that dissolution of solids proceeds with development of uniform, continuous frontiers of reaction.However this point of view is doubtful / 1 /. E.g. we have proved the active role of the block (grain) boundaries in the main phases of cement, these boundaries being the areas of hydrate phases' nucleation / 2 /. It has brought to the supposition that the dissolution frontier of cement particles in water is discrete. It seems also probable that the dissolution proceeds through the channels, which serve both for the liquid phase movement and for the drainage of the incongruant solution products. These channels can be appeared along the block boundaries.In order to demonsrate it, we have offered the method of phase-contrast impregnation of the hardened cement paste with the solution of methyl metacrylahe and benzoyl peroxide. The viscosity of this solution is equal to that of water.

Carbide precipitation and chromium depletion on coherent twin boundaries in deformed 304 stainless steels

1992 ◽  
Vol 50 (2) ◽  
pp. 1216-1217
Author(s):  
A.H. Advani ◽  
L.E. Murr ◽  
D.J. Matlock ◽  
W.W. Fisher ◽  
P.M. Tarin ◽  
...  
Keyword(s):  
Grain Boundaries ◽  
Stainless Steels ◽  
Interfacial Free Energy ◽  
Carbide Precipitation ◽  
Twin Boundaries ◽  
Invariant Structure ◽  
Heat Treated ◽  
Constant Structure ◽  
Cr Depletion

Coherent annealing-twin boundaries are constant structure and energy interfaces with an average interfacial free energy of ∼19mJ/m2 versus ∼210 and ∼835mJ/m2 for incoherent twins and “regular” grain boundaries respectively in 304 stainless steels (SS). Due to their low energy, coherent twins form carbides about a factor of 100 slower than grain boundaries, and limited work has also shown differences in Cr-depletion (sensitization) between twin versus grain boundaries. Plastic deformation, may, however, alter the kinetics and thermodynamics of twin-sensitization which is not well understood. The objective of this work was to understand the mechanisms of carbide precipitation and Cr-depletion on coherent twin boundaries in deformed SS. The research is directed toward using this invariant structure and energy interface to understand and model the role of interfacial characteristics on deformation-induced sensitization in SS. Carbides and Cr-depletion were examined on a 20%-strain, 0.051%C-304SS, heat treated to 625°C-4.5h, as described elsewhere.

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