Rate Of Water Penetration Research Articles

The Effect of Soil Conditioners on Water Movement through Lateritic Sandy Loam Soil

AbstractThe lateritic sandy loam soil of Gopali suffers by a high infiltration rate and percolation loss. The investigated soil was treated by four soil conditioners, CMC, PVA. Guargum and Lignosulphonate (LIG.) at 0.05 per cent and 0.10 per cent concentration level. The infiltration of water at −2 m bar pressure in horizontal column of soil was studied. The experimental results indicate that the lignosulphonate has increased the time by 30% and 70% to penetrate the 15 cm depth of soil column at 0.05 and 0.10 per cent concentration level, respectively. In the case of PVA, increase of time was 18 per cent and 33 percent at these the concentration level. Guargum at high concentration level increased the time by 31 per cent to penetrate the same depth of soil. Whereas CMC at high concentration reduced the time by 8 per cent. Similar trends were found in case of volume of water penetration and infiltration rate of treated soil.

Technique of measuring rapid water penetration rate into tablets.

Technique of measuring rapid water penetration rate into tablets.

IMPROVEMENT OF SOIL PROPERTIES AND PLANT GROWTH ON A BROWN SOLONETZIC SOIL USING IRRIGATION, CALCIUM AMENDMENTS AND NITROGEN

A 4-yr study was conducted on an irrigated Brown Solonetzic soil in southern Alberta to determine the effects of relatively low rates (4.2 Mg Ca ha−1) of surface-applied gypsum (CaSO4·2H2O) and lime (CaCO3) on soil chemical properties, water penetration and growth of bromegrass (Bromus inermis Leyss). Annual applications (155 kg N ha−1) of ammonium nitrate (NH4NO3) and ammonium bisulphite (NH4HSO3) were applied alone and in combination with the Ca amendments. Gypsum improved the chemical condition of the Bnt horizon by decreasing soluble Na and the electrical conductivity, and increasing levels of exchangeable Ca. The exchangeable Ca to Na ratio was increased from 5.5 to 16.9, while the sodium adsorption ratio was reduced from 18.1 to 7.6. Gypsum also decreased the EC of the Csk horizon from 12.7 to 5.2 dS m−1. In contrast, the lime amendment only increased the exchangeable Ca level of the Bnt horizon. Ammonium bisulphite decreased the soil pH of the soil profile, especially the Ap horizon (7.3–6.3), and increased the initial rate of water penetration into the Bnt horizon. Gypsum increased by threefold the rate of water infiltration into the Bnt horizon compared with the control soil. Plant yields were increased over the control by ammonium bisulphite (46%), ammonium nitrate (66%), gypsum (77%) and gypsum plus ammonium nitrate (111%). The study indicates that a combination of irrigation with gypsum was capable of moving Ca into a relatively high sodic Bnt horizon, causing an improvement in both the soil condition and plant productivity. Key words: Solonetzic soil, irrigation, gypsum, lime, sodic soil, ammonium nitrate

Water Uptake and Disintegrating Force Measurements: Towards a General Understanding of Disintegration Mechanisms

Water penetration and disintegrating force measurements were combined with the aim of assessing the role played by various mechanisms in the disintegration process.Nine tablet series, made of differing base materials (α-lactose monohydrate, dicalcium phosphate dihydrate and acetylsalicylic acid) such as are likely to elicit differing disintegration mechanisms and containing differing disintegrates in varying percentages were prepared and checked for Water penetration, disintegrating force development and disintegration time.The results obtained show that, in tablets made of dicalcium phosphate dihydrate or acetylsalicylic acid, a correlation exists between disintegration time and disintegrating force kinetics, which indicates that active mechanisms play the prevailing role in the disintegration process.On the contrary, the lack of such a correlation in lactose monohydrate tablets indicates that passive mechanisms are also involved in the disintegration process and prevail over active mechanisms. In this case, water penetration rate, rather than disintegrating force development rate, seems to be the governing factor in the disintegration process.

Reaction of zirconium fluoride glass with water: kinetics of dissolution

When liquid water contacts a zirconium-barium-lanthanum fluoride glass, at least three different processes occur. Barium and zirconium fluoride dissolve into the water, water penetrates into the glass, and zirconium fluoride crystals grow on the glass surface, in static solution. The rate of dissolution, as measured by solution analysis, is possibly controlled by diffusion in the solid surface; surface blockage and surface reactions are other possible kinetic steps involved. Diffusion in solution is not the controlling mechanism. Hydrogen profiles in the glass surface suggest that the penetration rate of water into the glass is controlled by diffusion and a surface reaction.

Dynamics of water, temperature, and salts in typical aridic soils after artificial rainstorms

In order to learn more about soil genesis, and ecology in the extremely dry desert of southwestern Egypt, we carried out irrigation experiments at four sites representing four typical (Solonchak and Yermosol) types of soil occurrence in this region. The irrigations simulated the rare episodic rainstorms. We measured water content, temperature, and salt content at various depths in the soil profiles for several weeks, at first hourly, then daily; we also observed changes in soil morphology. Thus, we obtained the rates of evaporation, water penetration, and salt migration at these sites. We speculate on the meaning of these data regarding soil genesis, and ecology in hyperarid deserts.

Effect of Electrolytic Concentration on the Hydraulic Properties of Depositional Crust

AbstractDepositional crusts form when turbid water infiltrates into soil. These crusts reduce the rate of water penetration. Hydraulic conductivity of two California soils was measured as a function of volume of suspension infiltrated and electrolytic concentration in the range ≤ 0.005 M. Whereas the hydraulic conductivity of the bulk soils was not affected by electrolytic concentration; the hydraulic conductivity of the soil columns with depositional crust increased by two orders of magnitude as the electrical conductivity (EC) of the suspension increased from 0.1 to 0.55 dS m−1. Saturated hydraulic conductivity of depositional crust made of flocculated particles was much higher than saturated hydraulic conductivity (HC) of crust made of dispersed clay and silt particles. Drying of the crusted soils destroyed the crust and restored the rate of water penetration. The curves of water penetration in consecutive irrigations were similar to that in the first irrigation. Phosphogypsum maintained high water penetration in three consecutive irrigations by increasing the electrolytic concentration in the solution above the clay flocculation values.

Dynamics of water, temperature, and salts in typical aridic soils after artificial rainstorms

Summary In order to learn more about soil genesis, and ecology in the extremely dry desert of southwestern Egypt, we carried out irrigation experiments at four sites representing four typical (Solonchak and Yermosol) types of soil occurrence in this region. The irrigations simulated the rare episodic rainstorms. We measured water content, temperature, and salt content at various depths in the soil profiles for several weeks, at first hourly, then daily; we also observed changes in soil morphology. Thus, we obtained the rates of evaporation, water penetration, and salt migration at these sites. We speculate on the meaning of these data regarding soil genesis, and ecology in hyperarid deserts.

Dissolution behavior of flufenamic acid dispersed in cross-linked insoluble polyvinylpyrrolidone: Effect of water-soluble polymers added as the third component.

Dissolution profiles of flufenamic acid (FFA) dispersed in cross-linked insoluble polyvinylpyrrolidone (polyvinylpolypyrrolidone, PVPP) were investigated by a dispersed amount method. The concentration of FFA rose very quickly and then decreased gradually, showing a typical supersaturation phenomenon. On the other hand, no supersaturation phenomenon was observed in the case of samples prepared with crystalline cellulose and potato starch as carriers in solid dispersions. In an attempt to stabilize the supersaturated state, the effects of the addition of water-soluble polymers to solid dispersions of FFA and PVPP were investigated. An adequate stabilization was obtained by the addition of methyl celluloses. Analysis of factors affecting the dissolution profiles of FFA and prediction of the dissolution behavior of FFA were carried out by a statistical technique. It was found that the penetration rate of water into sample powders, the amount of FFA adsorbed by PVPP, the cohesion tendency of sample powders the viscosity of the dissolution medium were important in the analysis of dissolution mechanisms and prediction of dissolution profiles of FFA from these systems.

A Spectroscopic (ATR) Approach to the Behaviour of Proline- and Sucrose-treated Biomembranes Towards Dehydratation and Rewatering

Summary A new spectroseopic (ATR) approach is suggested for investigating the state of water molecules in biological membranes under dehydratation and rewatering conditions. It is shown that the experimental systems water-thylakoid membranes, water-thylakoids-sucrose and water-thylakoidsproline differ in the extent of hydrogen bonding and water penetration rates. The method and devices are described.

Effect of Monoglyceride on Some Rehydrating Properties of Potato Granules

AbstractMonoglyceride incorporation in an Add‐Back (A – B) or Freeze‐Thaw (F – T) process decreases the potato granules Blue Value Index (BVI), Swelling Power (SP), rehydration rate and Water Binding Capacity (WBC), and increases the intact sound cell count. With 0.2% monoglyceride, SP, WBC and rehydration rate of A – B granules were 8.4, 6.7 and 6.4%, respectively, lower than F – T granules, while the BVI of A – B granules was 25.3% higher. Monoglyceride increase above 0.2% caused negligible changes. The intact sound cell count was higher when a precooking step was applied. The porous F – T and compact A – B granule structures partially accounted for differing water penetration rates. X‐ray analysis revealed a weak monoglyceride‐starch interaction during processing.

Release mechanisms in gelforming sustained release preparations

A system consisting of quinidine sulfate, excipient and gum (in various concentrations) was tested in tablet form. The insensitivity of this system to (a) the nature of the excipient and (b) the pH of the dissolution liquid is noted. The release mechanism is established as being limited by the rate of water penetration and back diffusion of the dissolved substance, whereas gelation rates and actual dissolution rate of the drug are not rate determining.

The influence of endosperm structure, protein content and grain moisture on the rate of water penetration into wheat during conditioning

SummaryThe effect of protein content, endosperm structure and grain moisture on the rate of water penetration into wheat grains was studied. Other factors which are known to alter the rate of water penetration were kept constant. an increase in the amount of endosperm protein was found to increase the time required to establish an equilibrium distribution of water regardless of whether the additional protein was present as discrete masses in the sub‐aleurone cells or throughout the entire endosperm. Grain moisture also influenced the rate at which any subsequent water passed through the endosperm. Moisture equilibrium was achieved more rapidly in those grains with a higher initial moisture content.

Influence of the Processing on the Surface Structure of Potato Granules as Viewed by SEM

AbstractFormation of the final surface structure of potato granules during the drying cycle of the freezethaw process is observed by scanning electron microscope. The cause of the formation of aggregates, polished cells, cemented granules and shrunken potato cells is discussed. The attention is given to the influence of surface structure on the rate of water penetration into the granules.

Effect of dimethyl sulfoxide on permeability of human skin In vitro

A diffusion flow cell is described for the continuous monitoring of skin permeability. The technique was used to study the permeability behavior of human skin subsequent to treatment with dimethyl sulfoxide. Such treatment produced an increased penetration rate of tritiated water, which was dependent upon the time of exposure and the concentration of dimethyl sulfoxide applied. Removal of the solvent resulted in partial recovery of barrier capacity. Skin, incubated in vitro in growth medium containing dimethyl sulfoxide, survived only at very low concentrations. Degeneration occurred after a few days in 4.5% dimethyl sulfoxide and much sooner at higher concentrations.

Effect of Surface Applied Sulfuric Acid on Water Penetration into Dry Calcareous and Sodic Soils

AbstractSulfuric acid, a surplus by‐product of copper smelters in the Southwest, was studied to determine a possible role in reclamation and revegetation of calcareous and sodic range soils. The rate of water penetration into dry calcareous soils was measured in columns as well as boxes after concentrated (93%) sulfuric acid was applied to the soil surfaces. The rate of penetration increased with increasing acid application rates, but then decreased, with optimum application rates ranging from 5 to 15 metric tons/ha. Acid was especially effective in increasing the rate of penetration into sodium‐affected calcareous soils. When acid was applied as a band on the soil surface, the wetting front advanced in an elongated semicircular form with depth. Surface applied acid was more effective than surface applied gypsum in increasing water penetration into sodiumsaturated soils. Sulfuric acid may be useful for increasing water penetration into and subsequently aiding in revegetation of sodium‐affected soils of semi‐arid regions.

Conditioning studies on Australian wheat. IV. Compositional variations in the bran layers of wheat and their relation to milling.

AbstractAnalysis of hand dissected bran and detergent fibre from six Australian wheat cultivars has shown that the rate of water penetration into grains during conditioning for milling, may in part be explained by some aspects of chemical composition of the bran. The degree of branching in bran arabinoxylans appears to be important; the more highly branched polysaccharides providing a greater barrier to water movement. The lipids may also cause a retardation of water movement through the bran layers of the wheat grain.

Conditioning studies on Australian wheat. III. The role of the rate of water penetration into the wheat grain

AbstractThe penetration of water into the grain of a number of wheat varieties at various time intervals after damping was followed using the technique of autoradiography. Significant varietal differences were noted in the rate of water penetration and these were found to relate closely to the milling behaviour of the respective varieties at the various time intervals after damping.

Water Penetration of Vineyard Soils as Modified by Cultural Practices

Extensive acreage of vineyard soils in the San Joaquin Valley appears to have poor and unstable structure which deteriorates upon contact with water. Water may cause deterioration of these aggregates in two ways: first, hydration which disperses the soil structure through swelling; and second, physical breakdown of the aggregates due to the erosive action of the moving water. The dispersed particles are carried into the upper soil pores and precipitate on the surface as a crust. Use of high electrolyte irrigation water and addition of gypsum to the soil increased the rate of water penetration. Aside from that, rate of water penetration was in direct proportion to the degree of soil crust prevention. A cover crop and organic matter added to the soils improved the rate of water penetration as long as a crust did not dominate. Penetration appeared to improve when the soil crust was disturbed by mechanical means.

Water Infiltration Control: a Channel System Concept

AbstractA channel system concept of infiltration was developed to describe the profound influence of large soil pores on the movement of soil water and air. This concept hypothesizes that soil surface conditions or channel system states control the flow of water and air in subsurface networks of large pores. Six channel system states (A through F), representing common soil surface conditions, form the basis for controlling infiltration within a range often exceeding one order of magnitude. Channel system states A, B and C represent rough surfaces with open, constricted and closed channel ports, respectively; whereas states D, E and F represent smooth surfaces with open, constricted and closed channel ports. Infiltration rates usually vary in the order A>B≃D>C≃E>F. Under state A the soil surface and subsurface channels are hydraulically and pneumatically connected, and under state F they are disconnected. Under state A water penetration rates are rapid and flow routes are relatively direct, whereas under state F rates are slow and routes are extremely tortuous. Soil surface management can be directed to achieving the desired channel system state and hence the design level of infiltration. The channel system concept appears applicable to a wide range of infiltration‐related problems.