The Plastic-Elastic behavior of Ebonite

1942 ◽  
Vol 15 (4) ◽  
pp. 826-834 ◽  
Author(s):  
J. R. Scott
Keyword(s):  
Low Temperature ◽  
Temperature Stability ◽  
Elastic Behavior ◽  
Temperature Sensitive ◽  
Probable Structure ◽  
Two Phase ◽  
Time Effects ◽  
Heat Stable ◽  
Plastic Yield ◽  
Sensitive Phase

Abstract A hypothesis is put forward to explain the plastic-elastic behavior of ebonite and its dependence on temperature. This is based on the previously described mechanical conception of ebonite as a system comprising a heat-stable elastic phase and a viscous temperature-sensitive phase, but the difficulty of reconciling this two-phase concept with the probable structure of ebonite is avoided by replacing the elastic and viscous phases respectively by primary and secondary (cohesional) bonds, the relaxation of the latter, due to their relatively low temperature-stability, being responsible for all time effects in the deformation of ebonite. The hypothesis explains the main facts relating to so-called plastic yield and to the residual strain after recovery from deformation, and thus appears to form a useful basis for further research on ebonite.

Exsolution and inversion in pigeonite from the Whin Sill, Northern England

1978 ◽  
Vol 36 (1) ◽  
pp. 474-475
Author(s):  
P.P.K. Smith
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Homogeneous Nucleation ◽  
Silicate Mineral ◽  
Antiphase Boundaries ◽  
Two Phase ◽  
Primitive Form ◽  
The Core ◽  
Nucleation Mechanisms ◽  
And Inversion

Grains of pigeonite, a calcium-poor silicate mineral of the pyroxene group, from the Whin Sill dolerite have been ion-thinned and examined by TEM. The pigeonite is strongly zoned chemically from the composition Wo8En64FS28 in the core to Wo13En34FS53 at the rim. Two phase transformations have occurred during the cooling of this pigeonite:- exsolution of augite, a more calcic pyroxene, and inversion of the pigeonite from the high- temperature C face-centred form to the low-temperature primitive form, with the formation of antiphase boundaries (APB's). Different sequences of these exsolution and inversion reactions, together with different nucleation mechanisms of the augite, have created three distinct microstructures depending on the position in the grain.In the core of the grains small platelets of augite about 0.02μm thick have farmed parallel to the (001) plane (Fig. 1). These are thought to have exsolved by homogeneous nucleation. Subsequently the inversion of the pigeonite has led to the creation of APB's.

A Comparison of Tem and Apfim to the Interpretation of Modulated Microstructures

1985 ◽  
Vol 43 ◽  
pp. 70-71
Author(s):  
M.G. Burke ◽  
M.K. Miller
Keyword(s):  
Low Temperature ◽  
Microstructural Characterization ◽  
Superlattice Reflection ◽  
High Volume ◽  
Atom Probe ◽  
Dark Field ◽  
Miscibility Gap ◽  
Second Phase ◽  
Two Phase ◽  
Probe Field

Interpretation of fine-scale microstructures containing high volume fractions of second phase is complex. In particular, microstructures developed through decomposition within low temperature miscibility gaps may be extremely fine. This paper compares the morphological interpretations of such complex microstructures by the high-resolution techniques of TEM and atom probe field-ion microscopy (APFIM).The Fe-25 at% Be alloy selected for this study was aged within the low temperature miscibility gap to form a <100> aligned two-phase microstructure. This triaxially modulated microstructure is composed of an Fe-rich ferrite phase and a B2-ordered Be-enriched phase. The microstructural characterization through conventional bright-field TEM is inadequate because of the many contributions to image contrast. The ordering reaction which accompanies spinodal decomposition in this alloy permits simplification of the image by the use of the centered dark field technique to image just one phase. A CDF image formed with a B2 superlattice reflection is shown in fig. 1. In this CDF micrograph, the the B2-ordered Be-enriched phase appears as bright regions in the darkly-imaging ferrite. By examining the specimen in a [001] orientation, the <100> nature of the modulations is evident.

scholarly journals C-Terminal Deletions Can Suppress Temperature-Sensitive Mutations and Change Dominance in the Phage Mu Repressor

Genetics ◽  
1996 ◽  
Vol 142 (3) ◽  
pp. 661-672 ◽  
Author(s):  
Jodi L Vogel ◽  
Vincent Geuskens ◽  
Lucie Desmet ◽  
N Patrick Higgins ◽  
Ariane Toussaint
Keyword(s):  
Binding Activity ◽  
Temperature Sensitive ◽  
Dna Binding Activity ◽  
Heat Stable ◽  
C Terminus ◽  
Acid Domain ◽  
Mutant Forms ◽  
Amino Acid Domain

Abstract Mutations in an N-terminal 70-amino acid domain of bacteriophage Mu's repressor cause temperature-sensitive DNA-binding activity. Surprisingly, amber mutations can conditionally correct the heat-sensitive defect in three mutant forms of the repressor gene, cts25 (D43-G), cts62 (R47-Q and cts71 (M28-I), and in the appropriate bacterial host produce a heat-stable Sts phenotype (for survival of temperature shifts). Sts repressor mutants are heat sensitive when in supE or supF hosts and heat resistant when in Sup° hosts. Mutants with an Sts phenotype have amber mutations at one of three codons, Q179, Q187, or Q190. The Sts phenotype relates to the repressor size: in Sup° hosts sts repressors are shorter by seven, 10, or 18 amino acids compared to repressors in supE or supF hosts. The truncated form of the sts62-1 repressor, which lacks 18 residues (Q179–V196), binds Mu operator DNA more stably at 42° in vitro compared to its full-length counterpart (cts62 repressor). In addition to influencing temperature sensitivity, the C-terminus appears to control the susceptibility to in vivo Clp proteolysis by influencing the multimeric structure of repressor.

scholarly journals Efforts towards a low-temperature-sensitive physics package for vapor cell atomic clocks

2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Qiang Hao ◽  
Wenxiang Xue ◽  
Feng Xu ◽  
Kemu Wang ◽  
Peter Yun ◽  
...  
Keyword(s):  
Low Temperature ◽  
Temperature Sensitive ◽  
Atomic Clocks ◽  
Vapor Cell

scholarly journals Performance and Microstructure of Cold Recycled Mixes Using Asphalt Emulsion with Different Contents of Cement

Materials ◽  
2019 ◽  
Vol 12 (16) ◽  
pp. 2548 ◽  
Author(s):  
Yanhai Yang ◽  
Ye Yang ◽  
Baitong Qian
Keyword(s):  
Low Temperature ◽  
Temperature Stability ◽  
Hydration Products ◽  
High Temperature Stability ◽  
Asphalt Emulsion ◽  
Moisture Susceptibility ◽  
Pavement Maintenance ◽  
Maintenance And Rehabilitation ◽  
Low Temperature Cracking ◽  
Temperature Crack

Cold recycled mixes using asphalt emulsion (CRME) is an economical and environmentally-friendly technology for asphalt pavement maintenance and rehabilitation. In order to determine the optimum range of cement contents, the complex interaction between cement and asphalt emulsion and the effects of cement on performance of CRME were investigated with different contents of cement. The microstructure and chemical composition of the fracture surface of CRME with different contents of cement were analyzed in this paper as well. Results show that the high-temperature stability and moisture susceptibility of CRME increased with the contents of cement increasing. The low-temperature crack resistance ability gradually increased when the content of cement is increased from 0% to 1.5%. However, it gradually decreased when the content of cement is increased from 1.5% to 4%. Cold recycled mixes had better low-temperature cracking resistance when the contents of cement were in the range from 1% to 2%. The results of microstructure and energy spectrum analysis show that the composite structure is formed by hydration products and asphalt emulsion. The study will be significant to better know the effects of cement and promote the development of CRME.

Oxidation and low temperature stability of vegetable oil-based lubricants

2006 ◽  
Vol 24 (3) ◽  
pp. 292-299 ◽  
Author(s):  
Sevim Z. Erhan ◽  
Brajendra K. Sharma ◽  
Joseph M. Perez
Keyword(s):  
Low Temperature ◽  
Vegetable Oil ◽  
Temperature Stability

Development of low temperature curing, 120°C, durable, corrosion protection powder coatings for temperature sensitive substrates

2005 ◽  
Vol 2 (8) ◽  
pp. 661-668 ◽  
Author(s):  
Glen Merfeld ◽  
Steve Mordhorst ◽  
Rainer Koeniger ◽  
A. Ersin Acar ◽  
Chris Molaison ◽  
...  
Keyword(s):  
Low Temperature ◽  
Corrosion Protection ◽  
Temperature Sensitive ◽  
Powder Coatings
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