Gel treatment is one of the most promising remedy methods to improve conformance in heterogeneous reservoirs for better sweep efficiency. In this paper, new enhanced preformed particle gels (PPGs) for conformance control at the Balal reservoir are introduced. In these PPGs, three species of 2-acrylamido-2-methylpropane sulfonic sodium salt (AMPSNa), acrylamide (AM) and N-vinylpyrrolidone (NVP) monomers have been used to synthesize via free radical crosslinking polymerization at room temperature using N, N-methylenebis (acrylamide) (MBA) as a cross linker. The swelling properties of the PPGs were enhanced by adding the Nano clay Montmorillonite Na+. A temperature stability agent was also used to make these special PPGs compatible with high temperature and salinity reservoir conditions. Then, PPGs were kept in Balal reservoir conditions in order to study their stability in harsh reservoir conditions. To this end, combination of 50 samples of the preformed particle gel has already been constructed by design of experiment using response surface method, and finally a new model for predicting the swelling ratio of the preformed particle gel based on the weight percentage of material and in different salinity is provided. The results of this research show that the crosslink has more influence on the swelling ratio, and PPG with the optimal formulation will able to guarantee the hard reservoir conditions (temperature 82˚ C & salinity 260000ppm).

Basil seed with mucilage shell contains carbohydrates (BSG) which can be extracted to produce natural hydrogel compatible with the human body. In this study, a magnetic natural hydrogel was synthesized by copolymerization between the double bonds of vinyl-modified Fe3O4/SiO2 nanoparticles, methacrylic acid (MA) as a monomer, ethylene glycol dimethacrylate (EGDMA) as a crosslinker monomer, and vinylated BSG through free radical addition polymerization for delivery of naproxen (NPX) as a model drug. The product of each reaction step was identified by FTIR technique and the morphology of nanoparticles and magnetic nano-hydrogels was investigated using the SEM technique. SEM image analysis of dry magnetic hydrogels shows the existence of a porous structure with pore size in the range of 100–, 300 nm. The porosity of the hydrogels used in drug delivery systems can be useful in producing a large surface area, enhancing water absorption, and facilitating drug release. The swelling behavior of nano-hydrogels, a significant feature for drug delivery systems, was investigated at different pHs in buffer solutions. Also, drug loading and delivery experiments were performed by monitoring the concentration of loaded and released NPX by absorption at 245 nm on a UV–, Vis spectrophotometer. The cumulative release behavior of hydrogels was investigated and the in vitro NPX release was achieved in the range of 98% at pH 7. 4 after 24 h.

Biomaterials having stimuli response are interesting in the biomedical field. This paper reports about swelling response and internal structural of biomineralized (CaCO3) polyvinylpyrrolidone (PVP) carboxymethylcellulose (CMC) hydrogel having various thicknesses (0.1–0.4 mm). Samples were tested in aqueous solution using temperature ranges from 10 to 40 oC; pH varies from 4 to 9, time 60 min. In addition, an experiment was conducted in the presence of simulated biological solutions (SBS): glucose (GS), physiological fluid (PS) and urea (US) at temperature 37 oC and pH 7.5 for 180 min. It is noticed that the maximum swelling ratio reached in 30–40 oC at pH 7 in aqueous solution. Among biological fluids, the swelling ratio shows: US [PS [GS at temperature 37 oC, pH 7.5, time 150 min. The equilibrium swelling ratio of the test sample in SBS and their nonreformative apparent structure confirm that biomineralized (CaCO3) PVP–CMC hydrogel can be acclaimed for medical application like bone tissue engineering.

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.