A 40-year-old woman who has worked in a wool factory came to the emergency room with severe swelling of her face and eyelids since two days before. She had also difficulty in swallowing. She was hospitalized and appropriate treatment was started. On the third day of hospitalization, although she got generally better, she developed ulceration of her left eyelid. The treatment was continued and she was discharged in good health after seven days of treatment.

Expansive behavior is usually observed in soils, which contain fractions of clay minerals in their composition. Water absorption of clay particles and change of natural water content of soil up to plastic limit and down to shrinkage limit will cause significant volume change in expansive soil and will result in severe damages to the structures, buildings and foundations. Swelling potential is directly related to clay minerals activity and soil plasticity. Besides all the parameters expressing composition of soil, environmental conditions provide conditions to release the swelling potential.In the present study, in order to observe effects of soil mineralogy, plasticity, and compaction indices such as water content and dry unit weight, swelling behavior of five clay soils has been investigated. Results of experiments indicate that parameters like clay minerals, absorbed cations to clay sheets, plasticity index, clay size fraction, initial water content and dry density have significant influence on the swelling behavior of compacted clays.

The present investigation is concerned with the reflection and transmission of plane waves at a interface between two swelling porous elastic half-spaces in welded contact. It is found that their exist two longitudinal waves and two transverse waves. The expression for various amplitude ratios due to the incidence of longitudinal wave in solid (PS) /longitudinal wave in fluid (PF) / transverse wave in solid (SVS) / transverse wave in fluid (SVF) have been obtained and depicted graphically. It is found the amplitude ratios of reflected and transmitted waves are the functions of angle of incidence and are a effected by the swelling porousity of the media. Surface response at the interface have also been obtained. The results so obtained have been compared with (without swelling porous) elastic medium (EL).The present investigation has immense application in structural problems.

During the past decades, hydrogels have been introduced suitable as novel materials for a variety of applications such as biomedical engineering, sanitary products, agriculture, bioseparation, enhanced oil recovery, etc. They have been successfully used as superabsorbent materials and in drug delivery, cell encapsulation and tissue repair due to their high water content and consequent biocompatibility. Considering the fact that water retention in the hydrogels provides a suitable drug diffusion pathway; many hydrogel-based networks have been designed and fabricated as intelligent carriers of drugs. The rate and degree of hydrogel swelling are the most important parameters which control the release patterns of solvents and drugs from these polymeric networks. Therefore, the precise account of hydrogel behaviour as well as mathematical description of equilibrium swelling, dimensional changes due to solvent uptake, desorption and drug release profiles were the main objectives in many investigations. The objective of this manuscript is to give a brief review on existing mathematical models and theories in the field of hydrogel swelling as well as the description of the drug release mechanism from swelling-controlled networks. The most important properties of hydrogels relevant to their swelling behaviour as well as kinetics and thermodynamic of swelling are also presented.

Swelling and diffusion characteristics of GCL samples made in the laboratory were studied and the results compared with the results of an industrial GCL. A Swell-Diffusion apparatus was designed, fabricated, and used to perform the swelling and swelling-diffusion tests.  Two types of available local geotextiles (Types I and II) with an available low quality Bentonite (LQB) were used to fabricate two types of GCL’s in the laboratory (Types A and B E-GCLs). The effect of stitching, applied stress, and wetting procedure, was investigated in swelling tests.  For type A E-GCL, with no stitch and no applied stress, a maximum of 6 mm swell was observed. Under 12.5 kPa stress, the swell decreased to a maximum of 2 mm. When this GCL was stitched, a maximum of 1.8 mm and 1.4 mm swell with zero and 12.5 kPa stresses were shown, respectively.  The swelling results showed that the wetting procedure (from top, from bottom, and both ways) has a negligible effect in maximum swell.  The type B E-GCL (having better geotextile quality compared to type A) showed a maximum 2.3 mm swell with no stitch, and 1.6 mm swell when stitched. The industrial needle punched reinforced GCLs with high quality granular sodium bentonite, under 12.5 kPa stress and wetted from top and bottom, showed a maximum of 3 mm swell. The swell data obtained from these experiments are in reasonable agreement with the data reported in the literature for similar GCLs under comparable conditions. Diffusion experiments were performed for types A and B E-GCL’s, as well as for the industrial GCLs. The chloride diffusion coefficients for types A and B E-GCL’s ranged from 2.7x10-10 m2/s to 3.5x10-10 m2/s compared to 2.9x10-10 m2/s to 3.5x10-10 m2/s for the industrial GCLs, which is in good agreement.

This study focuses on the swelling potential and damage capacity of buildings and foundations constructed on expansive soils. The geotechnical properties of such soils are mainly controlled by moisture absorption and clay content, particularly the presence of montmorillonite. As moisture and clay minerals increase, so does the soil's swelling potential and ability to cause damage. Laboratory tests on disturbed and undisturbed samples reveal that swelling percentage, swelling pressure, and free swell are critical properties. These are measured using tests like free swell and one-dimensional oedometer tests. The study shows that free swell ranges from 100% to 150%, and swelling pressure is around 45 kPa. The linear swelling coefficient (COLE) for these soils, analyzed using Plaxis software, ranges from 0. 09 to 0. 14. The findings emphasize the need for soil stabilization, with drainage and water control proving most effective. Numerical modeling enhances accuracy in predicting uplift behavior in these soils.

In this work, a series of hydrogel nanocomposites were prepared by grafting acrylic acid and acrylamide on gelatin in the presence of Na-montmorillonite (Na-MMT) nanoparticles. The characterizations of hydrogel nanocomposites were examined by swelling experiments, Fourier transform infrared (FT-IR) spectroscopy, X-Ray diffraction (XRD) patterns and thermogravimetric analysis (TGA). Scanning electron microscopy (SEM) was used to study the morphology of the samples. Under the optimized conditions the maximum capacity of swelling in de-ionized water was found to be 375 g/g. In spite of the sensitivity of the hydrogel absorbency to environmental pH, these hydrogel nanocomposites interestingly do not show remarkable changes in wide range of pH (from pH 4 to 10).

The fast-swelling porous starch-g-poly (acrylic acid) (St-g-PAA) superabsorbents were prepared simply by free-radical graft polymerization between acrylic acid and potato starch in the aqueous phase by using Triton X-100 as the pore-forming agent. The porous superabsorbents were characterized by FTIR and scanning electron microscopy. The effects of weight ratio of acrylic acid to starch and the Triton X-100 content on water absorbency were investigated. In addition, the effects of Triton X-100 on swelling rate, water absorbency in 0.9 % NaCl and in the artificial urine solution, and reswelling ability were studied in detail. The superabsorbent prepared with an acrylic acid/starch ratio of 6:1 and a Triton X-100 content of 0.4 % has a water absorbency of 683 g g-1 in distilled water and 72.8 g g-1 in 0.9 % NaCl. The content of Triton X-100 has great influence on the water absorbency and the swelling rate. The porous sample prepared with 0.4 % Triton X-100 only needs about 5 min to reach 80 % of its equilibrium water absorbency which is obviously shorter in comparison with the nonporous sample (about 90 min). The porous samples also show nice urine absorbency and excellent reswelling ability. We believe the reported method may find some applications in preparing novel porous hydrogels.