Prediction of normal melting point of pure substances by a reference series method

Recent studies have shown the presence of voids in several face-centered cubic metals after neutron irradiation at elevated temperatures. These voids were found when the irradiation temperature was above 0.3 Tm where Tm is the absolute melting point, and were ascribed to the agglomeration of lattice vacancies resulting from fast neutron generated displacement cascades. The present paper reports the existence of similar voids in the body-centered cubic metals tungsten and molybdenum.

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The observation of nano-voids in Au thin films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126627 ◽

1987 ◽

Vol 45 ◽

pp. 366-367

Author(s):

William Krakow

Keyword(s):

Thin Films ◽

Melting Point ◽

Present Author ◽

Stacking Faults ◽

Damage Threshold ◽

Ionic Species ◽

Rare Gases ◽

Chain Defects ◽

Vacancy Chains ◽

Au Thin Films

It has long been known that defects such as stacking faults and voids can be quenched from various alloyed metals heated to near their melting point. Today it is common practice to irradiate samples with various ionic species of rare gases which also form voids containing solidified phases of the same atomic species, e.g. ref. 3. Equivalently, electron irradiation has been used to produce damage events, e.g. ref. 4. Generally all of the above mentioned studies have relied on diffraction contrast to observe the defects produced down to a dimension of perhaps 10 to 20Å. Also all these studies have used ions or electrons which exceeded the damage threshold for knockon events. In the case of higher resolution studies the present author has identified vacancy and interstitial type chain defects in ion irradiated Si and was able to identify both di-interstitial and di-vacancy chains running through the foil.

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Three-Dimensional Reconstruction of Two Forms of the Chaperonin GRO EL

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100180045 ◽

1990 ◽

Vol 48 (1) ◽

pp. 258-259

Author(s):

J.L. Carrascosa ◽

G. Abella ◽

S. Marco ◽

M. Muyal ◽

J.M. Carazo

Keyword(s):

Three Dimensional ◽

The Other ◽

Two Dimensional ◽

Series Method ◽

Three Dimensional Reconstruction ◽

Structural Components ◽

E Coli ◽

Dimensional Reconstruction ◽

Morphogenetic Factors ◽

Tilt Series

Chaperonins are a class of proteins characterized by their role as morphogenetic factors. They trantsiently interact with the structural components of certain biological aggregates (viruses, enzymes etc), promoting their correct folding, assembly and, eventually transport. The groEL factor from E. coli is a conspicuous member of the chaperonins, as it promotes the assembly and morphogenesis of bacterial oligomers and/viral structures.We have studied groEL-like factors from two different bacteria:E. coli and B.subtilis. These factors share common morphological features , showing two different views: one is 6-fold, while the other shows 7 morphological units. There is also a correlation between the presence of a dominant 6-fold view and the fact of both bacteria been grown at low temperature (32°C), while the 7-fold is the main view at higher temperatures (42°C). As the two-dimensional projections of groEL were difficult to interprete, we studied their three-dimensional reconstruction by the random conical tilt series method from negatively stained particles.

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Higher-melting-point polyolefines as flexible dielectrics

Proceedings of the Institution of Electrical Engineers ◽

10.1049/piee.1965.0265 ◽

1965 ◽

Vol 112 (8) ◽

pp. 1633

Author(s):

S. Verne

Keyword(s):

Melting Point

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