scholarly journals Efflux and Influx of Erythrocyte Water

1960 ◽  
Vol 44 (2) ◽  
pp. 227-233 ◽  
Author(s):  
Edwin G. Olmstead
Keyword(s):  
Cell Suspension ◽  
Water Content ◽  
Freezing Point ◽  
Rabbit Serum ◽  
Freezing Point Depression ◽  
Hypertonic Solutions ◽  
Measured Change

Rabbit erythrocytes were washed in buffered NaCl solutions isotonic with rabbit serum (Δt -0.558°C.) and suspended in buffered NaCl solutions of tonicity equidistant from intracellular tonicity (Δt = -0.558°C. ± 0.112°C.) of varying pH and incubated at varying temperatures. After incubation, the freezing point depression (Δt) was measured on the supernatant. Change in the Δt measured change in the water content of the extracellular solutions—water being withdrawn by erythrocytes (WI) from the hypotonic solutions and added (WE) to the hypertonic solutions. WE was always less than WI and was inversely proportional to the pH in the range 6.5–8.0. WE was significantly increased by lowering the temperature of the cell suspension to 4°C. WI was increased by raising or lowering the pH or raising the temperature of the cell suspension. WE x WI ≠ k. WE and WI were affected differently by changes in pH and temperature. It was concluded that WE and WE were probably under different physicochemical control.

scholarly journals Efflux of Red Cell Water into Buffered Hypertonic Solutions

1960 ◽  
Vol 43 (4) ◽  
pp. 707-712 ◽  
Author(s):  
Edwin G. Olmstead
Keyword(s):  
Freezing Point ◽  
Maximum Amount ◽  
Red Cells ◽  
Rabbit Serum ◽  
Hypertonic Solution ◽  
Red Cell ◽  
Supernatant Fluid ◽  
Freezing Point Depression ◽  
Cell Water ◽  
Hypertonic Solutions

Buffered NaCl solutions hypertonic to rabbit serum were prepared and freezing point depressions of each determined after dilution with measured amounts of water. Freezing point depression of these dilutions was a linear function of the amount of water added. One ml. of rabbit red cells was added to each 4 ml. of the hypertonic solutions and after incubation at 38°C. for 30 minutes the mixture was centrifuged and a freezing point depression determined on the supernatant fluid. The amount of water added to the hypertonic solutions by the red cells was calcuated from this freezing point depression. For each decrease in the freezing point of -0.093°C. of the surrounding solution red cells gave up approximately 5 ml. of water per 100 ml. of red cells in the range of -0.560 to -0.930°C. Beyond -0.930°C. the amount of water given up by 100 ml. of red cells fits best a parabolic equation. The maximum of this equation occurred at a freezing point of the hypertonic solution of -2.001°C. at which time the maximum amount of water leaving the red cells would be 39.9 ml. per 100 ml. of red cells. The data suggest that only about 43 per cent of the red cell water is available for exchange into solutions of increasing tonicity.

scholarly journals Application of the Generalized Clapeyron Equation to Freezing Point Depression and Unfrozen Water Content

2018 ◽  
Vol 54 (11) ◽  
pp. 9412-9431 ◽  
Author(s):  
Jiazuo Zhou ◽  
Changfu Wei ◽  
Yuanming Lai ◽  
Houzhen Wei ◽  
Huihui Tian
Keyword(s):  
Water Content ◽  
Freezing Point ◽  
Unfrozen Water ◽  
Freezing Point Depression ◽  
Clapeyron Equation ◽  
Unfrozen Water Content

scholarly journals Investigation into Freezing Point Depression in Soil Caused by NaCl Solution

Water ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 2232 ◽  
Author(s):  
Feng Ming ◽  
Lei Chen ◽  
Dongqing Li ◽  
Chengcheng Du
Keyword(s):  
Water Content ◽  
Water Activity ◽  
Salt Concentration ◽  
Freezing Point ◽  
Saline Soil ◽  
Initial Water Content ◽  
Freezing Point Depression ◽  
Initial Water ◽  
Important Indicator ◽  
Critical Water Content

Engineering practices illustrate that the water phase change in soil causes severe damage to roads, canals, airport runways and other buildings. The freezing point is an important indicator to judge whether the soil is frozen or not. Up to now, the influence of salt on the freezing point is still not well described. To resolve this problem, a series of freezing point tests for saline soil were conducted in the laboratory. Based on the relationship between the freezing point and the water activity, a thermodynamic model considering the excess Gibbs energy was proposed for predicting the freezing point of saline soil by inducing the UNIQUAC (universal quasi-chemical) model. The experimental results show that the initial water content has little influence on the freezing point if the initial water content is higher than the critical water content, while the freezing point decreases with the decrease of the water content if the initial water content is lower than the critical water content. Moreover, it is found that the freezing point is related to the energy status of liquid water in saline soils and it decreases with the increase of the salt concentration. Moreover, the freezing point depression of saline soil is mainly caused by the decrease of water activity. Compared with the other two terms, the residual term, accounting for the molecular interactions, has an obvious influence on the water activity. This result is helpful for understanding how salt concentration affects the freezing point of saline soil and provides a reference for engineering construction in saline soil areas.

Depression of freezing temperature of water and water solutions in porous materials

1989 ◽  
Vol 54 (10) ◽  
pp. 2644-2647 ◽  
Author(s):  
Petr Schneider ◽  
Jiří Rathouský
Keyword(s):  
Water Vapor ◽  
Porous Materials ◽  
Inorganic Salt ◽  
Freezing Point ◽  
Freezing Temperature ◽  
Inorganic Salts ◽  
Freezing Point Depression ◽  
Salt Solutions ◽  
Water Solutions

In porous materials filled with water or water solutions of inorganic salts, water freezes at lower temperatures than under normal conditions; the reason is the decrease of water vapor tension above the convex meniscus of liquid in pores. The freezing point depression is not very significant in pores with radii from 0.05 μm to 10 μm (about 0.01-2.5 K). Only in smaller pores, especially when filled with inorganic salt solutions, this depression is important.

scholarly journals Freezing point depression and freeze-thaw damage by nanofluidic salt trapping

2020 ◽  
Vol 5 (12) ◽  
Author(s):  
Tingtao Zhou ◽  
Mohammad Mirzadeh ◽  
Roland J.-M. Pellenq ◽  
Martin Z. Bazant
Keyword(s):  
Freezing Point ◽  
Freezing Point Depression ◽  
Freeze Thaw

Colloid osmotic pressure changes of dog's blood exposed to different mixtures of CO2 and air

1978 ◽  
Vol 44 (2) ◽  
pp. 254-257 ◽  
Author(s):  
Y. Kakiuchi ◽  
A. B. DuBois ◽  
D. Gorenberg
Keyword(s):  
Red Blood Cells ◽  
Osmotic Pressure ◽  
Cell Volume ◽  
Blood Cells ◽  
Freezing Point ◽  
Colloid Osmotic Pressure ◽  
Red Cell ◽  
Freezing Point Depression ◽  
Pressure Changes ◽  
Different Levels

Hansen's membrane manometer method for measuring plasma colloid osmotic pressure was used to obtain the osmolality changes of dogs breathing different levels of CO2. Osmotic pressure was converted to osmolality by calibration of the manometer with saline and plasma, using freezing point depression osmometry. The addition of 10 vol% of CO2 to tonometered blood caused about a 2.0 mosmol/kg H2O increase of osmolality, or 1.2% increase of red blood cell volume. The swelling of the red blood cells was probably due to osmosis caused by Cl- exchanged for the HCO3- which was produced rapidly by carbonic anhydrase present in the red blood cells. The change in colloid osmotic pressure accompanying a change in co2 tension was measured on blood obtained from dogs breathing different CO2 mixtures. It was approximately 0.14 mosmol/kg H2O per Torr Pco2. The corresponding change in red cell volume could not be calculated from this because water can exchange between the plasma and tissues.

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