conventional transdermal drug delivery systems (tdds) have been designed for drug delivery through the skin. these systems use the permeability property of stratum corneum, the outermost surface layer of the skin. applying polymeric micro and nanofibers in drug delivery has recently attracted great attention and the electrospinning technique is the preferred method for polymeric micro-nanofiber...

A study on the use of chemical conversion coating as a preparative technique for foam-based structured catalysts, in water gas shift reaction, is presented. The results showed significant correlation between textural properties structure and preparation technique, highlighting how suitable highly porous structures. In first part paper, performance two catalysts obtained by commercial aluminium ...

The canine omental bursa is a virtual cavity enclosed by the greater and lesser omentum. While previous representations of this bursa were always purely schematic, a novel casting technique was developed to depict the three-dimensional organization of the omental bursa more consistently. A self-expanding polyurethane-based foam was injected into the omental bursa through the omental foramen in ...

The objective of this study is to investigate an appropriate process to fabricate the wood-polyurethane hybrid composites [wood-polyurethane foam (PUF)]. Rigid PUFs that contain up to 20% wood flours were successfully fabricated from polymeric 4,4-diphenylmethane diisocyanate, polyols, silicone surfactant, dibutin dilaurate/ dimethylethanolamine catalysts, and distilled water (chemical blowing ...

Tannin/furanic rigid foams were modi ed by either polymeric 4,4’ diphenylmethane diisocyanate (pMDI) or a one-component polyurethane still presenting reactive isocyanate groups (PUR). Several di erent sequences of mixing the isocyanate and polyurethane with the chemicals used to prepare tannin-based foams were tested. Scanning electron microscopy (SEM) showed that addition of either pMDI or PUR...

The addition of less than 1 vol%, 33 nm zinc oxide nanoparticles into a polyurethane matrix resulted in approximately 40% decrease in the Young’s modulus, 80% decrease in strain at fracture, and 50% decrease in the storage modulus, but at the same time resulted in an w11 8C increase in the glass transition temperature of the polymer. These results appear to contradict the general principle obse...

Use of conventional flexible polymeric mould materials yields to longer solidification time of (wax/plastic) patterns in soft tooling process, thereby reducing the rapidity of the process to a great extent, which is not desirable in present competitive market. In this work, approach of particle-reinforcement with mould materials is introduced to reduce the cycle time of Soft tooling process and...

In poultry industry, cross-contamination due to processing equipment and contact surfaces is very common. This study examined the extent of bacterial attachment to 6 different types and design of conveyor belts: stainless steel-single loop, stainless steel-balance weave, polyurethane with mono-polyester fabric, acetal, polypropylene mesh top, and polypropylene. Clean conveyor belts were immerse...

We analyzed the interactions between human primary cells from pancreatic ductal adenocarcinoma (PDAC) and polymeric scaffolds to develop 3D cancer models useful for mimicking the biology of this tumor. Three scaffold types based on two biocompatible polymeric formulations, such as poly(vinyl alcohol)/gelatin (PVA/G) mixture and poly(ethylene oxide terephthalate)/poly(butylene terephthalate) (PE...

polyurethane foams are extensively used in different applications such as furnitures and sandwich structures due to better mechanical properties, higher acoustic and damping behavior, higher resistance to hydrocarbon, and aging.with respect to flammability of polyurethane materials and safety precaution in living and working environments there is a vital need to study and investigate published ...