Comparative Analysis of Water Retention Curves of Residual Soils of Gneiss, Granite and Diabase, Compacted under Optimum Moisture Conditions

A functional description of the hydrophysical properties of the soil as a capillary-porous medium is presented. The described functions of water retention capacity and hydraulic conductivity of the soil have common parameters, which are interpreted within the framework of physical and statistical concepts. The practical significance of the proposed functions lies in the fact that the volume of labor-intensive field measurements necessary, for example, for modeling the dynamics of soil moisture, is significantly reduced. To identify the parameters of these functions, it is sufficient to use data only on the water retention capacity of the soil. The parameters identified in this way can be used to predict the ratio of the hydraulic conductivity of the soil to the moisture filtration coefficient. The presented system of the hydrophysical functions of the soil is compared with world analogues using literature data on soils of different texture.

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Hybrid Reinforced Composite Material from Garbage to Biomaterials

International Journal of Innovative Technology and Exploring Engineering - Special Issue ◽

10.35940/ijitee.i8956.078919 ◽

2019 ◽

Vol 8 (9) ◽

pp. 3346-3349 ◽

Cited By ~ 3

Keyword(s):

Composite Material ◽

Impact Strength ◽

Water Retention ◽

Fine Powder ◽

Soaking Time ◽

Reinforced Composite ◽

Before And After ◽

Egg Shell ◽

Moisture Conditions ◽

Reinforced Composite Material

A hybrid reinforced composite material which fundamentally contains horticulture squander materials like banana stem outer layer (Musa sepientum) modified to powder form, egg shell modified to fine powder ,the said powders (powder have a size in a range of 10 to 50 microns) being mixed in a matrix of bio epoxy resin using a catalyst to effect complete mixing of the said powdered fibers to yield the said hybrid reinforced composite, the said hybrid composite capable of being molded to any geometrical object, the said composite having a low water retention property with retention being in a range of 14-23% with a soaking time of 120 hrs. Before and after chemical treatment in both with and without moisture, the youngs modulus varies from 12321.5241 N/mm2 to 25779.2532 N/mm2 , the flexural values varies from 17.4 N/mm2 to 25.5 N/mm2 ,impact strength varies from 12.6 J to 20.9 J , % of elongation varies from 5.6% to 10.1%. The composite has negligible change in tensile properties up to a load of 270 Kg also flexural properties and impact strength of the composite were not be affected by under moisture conditions.

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A trait based approach to bacterial biofilms in soil

10.7287/peerj.preprints.1637v1 ◽

2016 ◽

Author(s):

Jay T Lennon ◽

Brent K Lehmkuhl

Keyword(s):

Water Availability ◽

Water Retention ◽

Niche Construction ◽

Moisture Gradient ◽

Bacterial Biofilms ◽

Soil Environment ◽

Soil Water Retention ◽

Biofilm Production ◽

Moisture Conditions ◽

Growth And Reproduction

One of the greatest challenges of living in the soil environment is that microorganisms must contend with fluctuations in water availability. Biofilm production is a trait that may helps bacteria persist through moisture conditions that are suboptimal for growth and reproduction. Using an alginate knockout of Pseudomonas aeruginosa, we demonstrate that biofilm production increased survivorship and created a more favorable moisture niche. Although biofilm production is assumed to incur a fitness cost, we were unable to detect a trade-off along a moisture gradient. In addition to increasing desiccation tolerance, biofilm production altered the soil environment in ways that were consistent with niche construction. Specifically, biofilm production increased soil water retention, but this did not facilitate the growth of an unrelated, desiccation-sensitive soil bacterium. In sum, our findings suggest that biofilm production is a response and effect trait that may influence the distribution and abundance of microorganisms in soil environments.

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