Analysis of the state of water in polyvinylpyrrolidone aqueous solutions using DSC method

Data for the depression of vapour pressure are presented for the following aqueous solutions: NaCl (0.03 to 0.1 molar), KCl (0.03 to 0.1 molar), urea (0.05 to 0.5 molar), sucrose (0.05 to 0.10 molar), lactic and succinic acids, creatine, CaCl2 (0.05 molar), and mixtures of these substances with one another and with certain other solutions (gelatin, gum acacia, sea water, LiCl, etc.). The relation of the depression of vapour pressure of a mixed solution to that of solutions of the individual constituents was investigated in order to ascertain to what extent such studies may be used for the determination of the degree of hydration, or of the state of water, in solutions. Organic substances (urea, sucrose, etc.) showed anomalous results which were markedly affected and unpredictable in mixed solutions. They are, therefore, unsuited for the study of water binding. In the case of solutions of inorganic substances—LiCl and CaCl2—the principle of the additive nature of colligative properties is also only approximately true—except perhaps in very dilute solutions. The limitations of the colligative method for determining the degree of hydration have been defined in accord with the above findings. Studies of the vapour pressures of mixtures of gelatin or gum acacia with NaCl or KCl demonstrated that hydration in gelatin is relatively small at pH = 7 and undetectable in gum acacia solutions. The view, therefore, that hydrophilic colloids are strongly hydrated has not been substantiated. The passage from the sol to the gel state also was not accompanied in gelatin or in blood by any appreciable change in the degree of hydration of the hydrophilic colloids present in these substances.

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The state of water in acclimating vegetative buds from Malus and Amelanchier and its relationship to winter hardiness

Physiologia Plantarum ◽

10.1034/j.1399-3054.1992.860401.x ◽

1992 ◽

Vol 86 (4) ◽

pp. 503-511 ◽

Cited By ~ 1

Author(s):

Christina W. Vertucci ◽

Cecil Stushnoff

Keyword(s):

Winter Hardiness ◽

The State ◽

Vegetative Buds ◽

State Of Water

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ELECTRODYNAMIC SENSOR FOR ASSESSING TRANSFORMATIONS OF THE STATE OF WATER IN BIOLOGICAL OBJECTS

Telecommunications and Radio Engineering ◽

10.1615/telecomradeng.v77.i12.80 ◽

2018 ◽

Vol 77 (12) ◽

pp. 1103-1112

Author(s):

Ch. Liu ◽

I. N. Bondarenko ◽

A. Yu. Panchenko ◽

N. I. Slipchenko

Keyword(s):

The State ◽

Biological Objects ◽

State Of Water

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ELECTRODYNAMIC SENSOR FOR DETERMINING THE STATE OF WATER IN BIOLOGICAL OBJECTS

Telecommunications and Radio Engineering ◽

10.1615/telecomradeng.v78.i9.60 ◽

2019 ◽

Vol 78 (9) ◽

pp. 801-811

Author(s):

Ch. Liu ◽

I. N. Bondarenko ◽

A. Yu. Panchenko ◽

N. I. Slipchenko

Keyword(s):

The State ◽

Biological Objects ◽

State Of Water

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CONSIDERATION OF THE VALIDITY OF THE STATISTICAL CHARACTERISTICS OF pH IN SURFACE WATERS

Engineering survey ◽

10.25296/1997-8650-2019-13-2-52-58 ◽

2019 ◽

Vol 13 (2) ◽

pp. 52-58

Author(s):

V. B. Korobov ◽

I. V. Miskevich ◽

A. S. Lokhov ◽

K. A. Seredkin

Keyword(s):

Field Measurements ◽

Heavy Precipitation ◽

The State ◽

Statistical Characteristics ◽

Mean Values ◽

River Waters ◽

Ph Values ◽

State Of Water ◽

Environment Temperature ◽

Unit Characteristic

Abstract: pH is one of the most important parameters characterizing the state of water systems. The arithmetic mean values of samples are often used when averaging serial pH measurements in water bodies, as is usually done for other characteristics of the state of the natural environment (temperature, salinity, oxygen concentrations, suspended solids, etc.). However, in this case such an operation is illegal, since the addition of logarithms, which by definition are pH, is non-additive. The authors conducted a study to determine the extent to which pH variability in natural objects such an operation would not distort the results. For this, several samples of the pH index were generated in various ranges of its theoretically possible and natural variability. It was established that with pH variability of less than a unit characteristic of marine pH values, the statistical characteristics of the indicator and [H+ ] concentrations differ slightly, and the medians of the samples coincide. It is concluded that with such ranges characteristic of the waters of the oceans, there is no need to recalculate previously obtained results. However, for the estuaries of rivers flowing into tidal seas, as shown by field measurements, the pH variability in the mixing zone of sea and river waters is several times higher. Similar situations may occur when heavy precipitation falls on the water surface, as well as during floods. In these cases, a simple averaging of the pH values will no longer be correct. In such cases, the use of other averaging algorithms and the choice of stable statistical characteristics are required.

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