ON THE ABSENCE OF CONSTANT CORRELATION BETWEEN HEAT-RESISTANCE OF CELLS AND THE MELTING POINT OF THEIR LIPIDS

Three groups of goldfish were fed diets containing 25% fat. The diets for the three groups differed in the degree of unsaturation of these fats. Pilchard oil (iodine value 181.7), herring oil (iodine value 128.4), and lard (iodine value 66.2) were the fats used. Heat tolerance of the fish was then tested by holding them at a constant high temperature and observing the time of death. Variations in the ability of the groups to withstand high temperature were correlated with differences in the degree of unsaturation of their extracted fats. The iodine value of the herring oil diet was very close to that of the fats of the goldfish prior to feeding and no change in the value for fish fed on this diet was observed. Each of the other two diets changed the degree of unsaturation of the goldfish fats by approximately 54% of the maximum theoretical change. These changes modified the heat resistance of the fish. The degree of modification of heat tolerance, however, cannot be strictly correlated with the degree of change of unsaturation of fats and it is concluded that factors associated with differences in melting point rather than melting point of the fat itself are probably involved in heat resistance.

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Development of compositions from waste of polypropylene and polyethylene terephthalate and research of their technological and thermal properties

E3S Web of Conferences ◽

10.1051/e3sconf/202126405005 ◽

2021 ◽

Vol 264 ◽

pp. 05005

Author(s):

Bahodir Mukhiddinov ◽

Lola Tilavova ◽

Shokhruh Juraev

Keyword(s):

Thermal Properties ◽

Melting Point ◽

Heat Resistance ◽

Polyethylene Terephthalate ◽

Flow Rate ◽

Thermal Characteristics ◽

Solubility Parameters ◽

Melt Flow ◽

Melt Flow Rate ◽

Temperature Decomposition

The article presents the results of determining the melting point and the melt flow rate, Vicat heat resistance of a composition made of polypropylene waste from the study of polyethylene terephthalate. It has been established that with an increase in the content of polyethylene terephthalate, the melting point and heat resistance according to Vicat increase, and the melt flow rate of the compositions decreases. The Hildebrand solubility parameters and the packing density of macromolecules are calculated using the increment method. The thermal characteristics of the compositions were investigated by the derivatography method. Their decomposition onset temperature, decomposition rate, and the amount of energy consumed for the decomposition of polymers and polymer compositions were determined. It was revealed that the compositions of polyethylene terephthalate with secondary polypropylene are more thermostable than compositions of polyethylene terephthalate with primary polypropylene.

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Voids in Irradiated Tungsten and Molybdenum

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100062865 ◽

1969 ◽

Vol 27 ◽

pp. 190-191

Author(s):

Robert C. Rau ◽

Robert L. Ladd

Keyword(s):

Melting Point ◽

Fast Neutron ◽

Neutron Irradiation ◽

Elevated Temperatures ◽

Irradiation Temperature ◽

The Body ◽

Face Centered Cubic ◽

Body Centered Cubic ◽

Cubic Metals ◽

Face Centered

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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