Measurement of Hydraulic Conductivity of Frozen Soils

1974 ◽  
Vol 11 (4) ◽  
pp. 647-650 ◽  
Author(s):  
P. J. Williams ◽  
T. P. Burt
Keyword(s):  
Free Energy ◽  
Weak Solution ◽  
Hydraulic Conductivity ◽  
Soil Type ◽  
Pure Water ◽  
Frozen Soils

Frozen soils contain a significant amount of water which moves under appropriate gradients. An apparatus has been devised for measuring the hydraulic conductivity. It involves the use of reservoirs containing a weak solution of lactose such that the free energy is initially reduced to that of the water in the soil. The solution therefore remains unfrozen. A gradient is established by application of pressure, and pure water moves in the sample. The hydraulic conductivity is found to depend on soil type and temperature.

INFLUENCE OF AMMONIUM ON THE BEHAVIOR OF CLAY PARTICLES IN A SODIC SOIL AND BENTONITE

1974 ◽  
Vol 54 (1) ◽  
pp. 39-44 ◽  
Author(s):  
J. C. VAN SCHAIK ◽  
R. R. CAIRNS
Keyword(s):  
Hydraulic Conductivity ◽  
Beneficial Effect ◽  
Salt Concentration ◽  
Soil Type ◽  
Water Movement ◽  
Ammonium Salts ◽  
Sodic Soil ◽  
Clay Particles ◽  
Mobility Studies ◽  
Solonetz Soil

The addition of ammonium salts increased the hydraulic conductivity of samples taken from the Bnt horizon of a Solonetz soil. The improved conductivity was caused by an increase in the salt concentration in the soil solution and by the ammonium adsorbed on the clay particles. Since the dominant clay mineral in this soil type is montmorillonite, purified bentonite was used for comparative studies. Mobility studies of montmorillonite systems indicated that the adsorbed NH4 ions are tightly bound to the clay particles. The size of the NH4-tactoids was found to be larger than that of the Na-tactoids but less than half that of the Ca-tactoids. It was concluded that the beneficial effect of ammonium on water movement in Solonetz soils will be less than that of calcium, but the transformation of the adsorbed ammonium in the field, followed by replacement of sodium by hydrogen, may result in further improvement of these soils.

scholarly journals Soil type and land use effects on tensorial properties of saturated hydraulic conductivity in northern Germany

2019 ◽  
Vol 71 (2) ◽  
pp. 179-189 ◽  
Author(s):  
Rainer Horn ◽  
Anneka Mordhorst ◽  
Heiner Fleige ◽  
Iris Zimmermann ◽  
Bernd Burbaum ◽  
...  
Keyword(s):  
Land Use ◽  
Hydraulic Conductivity ◽  
Soil Type ◽  
Saturated Hydraulic Conductivity ◽  
Northern Germany ◽  
Land Use Effects

scholarly journals Micellisation behavior on the dodecyltrimethylammonium bromide in the presence of Brij-35 in pure water by conductivity measurement

BIBECHANA ◽  
2017 ◽  
Vol 15 ◽  
pp. 85-89
Author(s):  
Neelam Shahi ◽  
Ajaya Bhattarai
Keyword(s):  
Free Energy ◽  
Sharp Increase ◽  
Pure Water ◽  
Specific Conductivity ◽  
Aqueous Media ◽  
Conductivity Measurement ◽  
Ammonium Bromide ◽  
Dodecyltrimethylammonium Bromide ◽  
Brij 35 ◽  
Versus Concentration

Conductivity measurement of dodecyltrimethylammonium bromide in the presence of Brij-35 in aqueous media at 289.15 K is performed. The result showed a sharp increase in conductivity with increase in the concentration of dodecyltrimethylammonium bromide in the presence of Brij-35. The graph of specific conductivity versus concentration is used in determining the critical micelle concentration (CMC). There is the decrease in CMC of  dodecyltrimethylammonium bromide in the presence of  Brij-35 in comparison with the CMC of  dodecyltrimethyl ammonium bromide [DTAB]. Gibbs free energy of micellisation has also been evaluated.   BIBECHANA 15 (2018) 85-89

Note on the art of photography, or the application of the chemical rays of light to the purposes of pictorial representation

1843 ◽  
Vol 4 ◽  
pp. 131-133 ◽  
Keyword(s):  
Weak Solution ◽  
Pure Water ◽  
Solar Light ◽  
Pictorial Representation ◽  
Insoluble Compound ◽  
Lime Water ◽  
Oxidizing Power ◽  
The Subject

The author states that his attention was first called to the subject of M. Daguerre’s concealed photographic processes, by a note from Captain Beaufort, dated the 22nd of January last, at which time he was ignorant that it had been considered by Mr. Talbot, or by any one in this country. As an enigma to be solved, a variety of processes at once presented themselves, of which the most promising are the following; 1st, the so-called de-oxidizing power of the chemical rays in their action on recently precipitated chloride of silver; 2ndly, the instant and copious precipitation of a mixture of a solution of muriate of platina and lime-water by solar light, forming an insoluble compound, which might afterwards be blackened by a variety of agents; 3rdly, the reduction of gold in contact with deoxidizing agents; and, 4thly, the decomposition of an argentine compound soluble in water, exposed to light in an atmosphere of peroxide of chlorine, either pure or dilated. Confining his attention, in the present notice, to the employment of chloride of silver, the author inquires into the methods by which the blackened traces can be preserved, which may be effected, he observes, by the application of any liquid capable of dissolving and washing off the unchanged chloride, hut of leaving the reduced, or oxide of silver, untouched. These conditions are best fulfilled by the liquid hyposulphites. Pure water will fix the photograph, by washing out the nitrate of silver, but the tint of the picture resulting is brick red; but the black colour may be restored by washing it over with a weak solution of hyposulphite of ammonia.

scholarly journals Temperature deformation of frozensoils at sharp change of temperature

2017 ◽  
pp. 66-71
Author(s):  
S. S. Volokhov ◽  
I. N. Nikitin ◽  
D. S. Lavrov
Keyword(s):  
Temperature Change ◽  
Soil Type ◽  
Sudden Change ◽  
Frozen Soil ◽  
Temperature Deformation ◽  
Sharp Change ◽  
Frozen Soils ◽  
One Stage ◽  
Different Types ◽  
Number Of Cycles

The results are described of the study of temperature deformation of different types of frozen soil in the cycles of cooling-heating at sudden change in temperature. The differences in the nature of the temperature deformation at step and one stage temperature change are shown. The dependences are investigated of the temperature deformation of frozen soils on soil type, moisture and total number of cycles of cooling-heating.

On the prediction of hydraulic conductivity of frozen soils

1996 ◽  
Vol 33 (1) ◽  
pp. 176-180 ◽  
Author(s):  
Vlodek R Tarnawski ◽  
Bernhard Wagner
Keyword(s):  
Grain Size ◽  
Hydraulic Conductivity ◽  
Water Content ◽  
Bulk Density ◽  
Size Distribution ◽  
Grain Size Distribution ◽  
Input Data ◽  
Unfrozen Water ◽  
Frozen Soils ◽  
Unfrozen Water Content

This paper describes a mathematical model for predicting the hydraulic conductivity of partially frozen soils on the basis of limited input data such as grain size distribution and bulk density or porosity. A new model is based on an analogy for the hydraulic conductivity of frozen and unfrozen soils and models for the estimation of hydraulic properties of soils and unfrozen water content. Campbell's model was used for prediction of soil-water characteristics from limited data, while unfrozen water content was obtained from two models (by P.J. Williams and D.M. Anderson) applied to two different temperature ranges. The new model can be used for the rapid estimation of the hydraulic conductivity of practically any freezing soil having log-normal grain size distribution and for computer simulation of moisture migration in soils below the freezing point. An acceptable conformity between the model prediction and measured data for pure sand has been achieved. The computer program developed requires the following input data: grain size distribution, bulk density or porosity, and soil temperature. Key words: frozen soils, hydraulic conductivity, bulk density, grain size distribution, unfrozen water content.

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