Peculiar Thermodynamics of the Second Critical Point in Supercooled Water

2011 ◽  
Vol 115 (48) ◽  
pp. 14099-14111 ◽  
Author(s):  
C. E. Bertrand ◽  
M. A. Anisimov
Keyword(s):  
Critical Point ◽  
Supercooled Water

scholarly journals Аномалия микроволнового поглощения льда вблизи -45-=SUP=-o-=/SUP=-C при пластической деформации

2019 ◽  
Vol 89 (3) ◽  
pp. 452
Author(s):  
Г.С. Бордонский
Keyword(s):  
Plastic Deformation ◽  
Phase Space ◽  
Critical Point ◽  
Microwave Absorption ◽  
Atmospheric Pressure ◽  
Supercooled Water ◽  
Measuring Technique ◽  
Temperature Phase ◽  
Widom Line ◽  
Radiation Transmission

AbstractThe microwave absorption of fresh ice subjected to plastic deformation when changing temperature from 0 to –60°C has been measured. A decrease in the losses of radiation transmission through ice at frequencies of 32 and 125 GHz with extremum at a temperature of –45°C was found. This temperature corresponds to the point at atmospheric pressure at the Widom line, which starts from a hypothetic second critical point in pressure–temperature phase space. The used measuring technique makes it possible to obtain layers of deeply supercooled water into ice and study the position of the Widom line and second critical point in phase space.

scholarly journals Comparison of various models of supercooled water loss factor with experimental data at microwaves

2019 ◽  
pp. 104-112
Author(s):  
G. S. Bordonskiy ◽  
A. O. Orlov
Keyword(s):  
Experimental Data ◽  
Critical Point ◽  
Water Loss ◽  
Loss Factor ◽  
Supercooled Water ◽  
Significant Discrepancy ◽  
Deep Supercooling ◽  
Calculation Results ◽  
Adequate Representation ◽  
Silicate Materials

An improved formula for the supercooled water loss factor at frequencies 10…180 GHz in the temperature range 0 ... –70 °C is presented. The formula based on the experimental data obtained by the authors on measurements of attenuation in the pore water of silicate materials. The formula contains two terms connected the Debye dependence of the loss factor on frequency and temperature, and non-Debye, determined by the influence of the second critical point of water. Comparison of the proposed formula and the model formulas of other authors is carried out. A significant discrepancy between the calculation results (at several times) of the loss factor at frequencies above 100 GHz and temperatures below –30 °C has been founded. The model based on the measurements provides the most adequate representation of the behavior of the loss factor with an error of ~ 30% in the area of deep supercooling of water and in the upper part of the studied frequency band.

The Critical Point Drying Method Applied to Scanning Electron Microscopy of L-929 Cells

1970 ◽  
Vol 28 ◽  
pp. 278-279
Author(s):  
Charles TurnbiLL ◽  
Delbert E. Philpott
Keyword(s):  
Electron Microscopy ◽  
Carbon Dioxide ◽  
Surface Tension ◽  
Critical Point ◽  
Freeze Drying ◽  
Attractive Alternative ◽  
Crystal Formation ◽  
Critical Point Drying ◽  
Time Required ◽  
Scanning Electron

The advent of the scanning electron microscope (SCEM) has renewed interest in preparing specimens by avoiding the forces of surface tension. The present method of freeze drying by Boyde and Barger (1969) and Small and Marszalek (1969) does prevent surface tension but ice crystal formation and time required for pumping out the specimen to dryness has discouraged us. We believe an attractive alternative to freeze drying is the critical point method originated by Anderson (1951; for electron microscopy. He avoided surface tension effects during drying by first exchanging the specimen water with alcohol, amy L acetate and then with carbon dioxide. He then selected a specific temperature (36.5°C) and pressure (72 Atm.) at which carbon dioxide would pass from the liquid to the gaseous phase without the effect of surface tension This combination of temperature and, pressure is known as the "critical point" of the Liquid.

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