Dilute ( ~10% w/v) unsonicated phosphatidylserine dispersions in Hz0 contain spherical particles of a wide size distribution (0.1 to 15 q). The majority have diameters between 0.1 to 2 pm and lack the multilamellar arrangement of bilayers typical of unsonicated lecithin dispersions. Sonication uroduces small thermodynamically unstable vesicles surrounded by a single closed bilayer with an avera...

Manufacturing tolerancing is intended to determine the intermediate geometrical and dimensional states of the part during its manufacturing process. These manufacturing dimensions also serve to satisfy not only the functional requirements given in the definition drawing, but also the manufacturing constraints, for example geometrical defects of the machine, vibration and the wear of the cutting...

Corrosion is one of the major problems in the oil and gas industry is one that automatically allocates huge sums annually. Polyurethane is a thermoses polymer with various applications. Using form this polymer has spread for military applications by Otto Bayer in 1930. In one general look polyurethane is product of Iso Syanate and ploy with each other, So that: Iso + ploy = polyurethane. Spend ...

Silicone is a polymer widely used for medical purposes, including breast implants. The aim of this work is to verify the occurrence of silicone gel diffusion through the lining membrane (bleed) of gel breast implants with smooth, textured, and polyurethane foam coated surfaces, sterilized by dry heat and ethylene oxide. The results enable us to conclude that there is significant difference for ...

Comparing to the conventional bath heating, the effects of liquefaction parameters on the degree of liquefaction of wood in polyhydric alcohols by using microwave as an energy source were evaluated. Polyurethane foams were successfully prepared from the liquefied biomass-based polyols. The effects of heating methods (conventional bath heating and microwave) and liquefaction reaction time on the...

In this research scotch pine (Pinus sylvestris L.), Eastern beech (Fagus orientelis L.), oak (Quercus petraea L.) samples have been covered with polyurethane, acrylic, cellulosic varnish. In order to determine the physical changes which occurred on varnish layers caused by steam and wet heat, the samples were exposed to TS 4982 EN 12721 wet heat and TS EN 438-2 steam. According the results, the...

Spray application of polyurethane foam for thermal insulation of buildings represents the polyurethane application with the highest potential worker exposure to MDI. This paper reviews the existing work done to characterize the MDI exposures of the sprayed polyurethane foam workers as well as identifying several elements of an effective industrial hygiene program suggested by the existing work....

A previous study showed that microporous, compliant and (bio)degradable vascular prostheses prepared from a polyurethane/poly(L-lactic acid) mixture can function as a temporary scaffold for the regeneration of small-calibre arteries. In this study the mechanism of fragmentation of vascular prostheses made of polyurethane, copolyesterether and blends of either polyurethane or copolyesterether wi...

The objective of the study is to prepare, characterize and evaluate starch phosphate, a new modified starch as a carrier in solid dispersions for enhancing the dissolution rate of ritonavir. The feasibility of formulating solid dispersions of ritonavir in starch phosphate into compressed tablets with enhanced dissolution rate was also investigated. Starch phosphate was prepared by reacting star...

C-trim is a healthy food product containing soluble dietary fibre β-glucan. The dispersion of C-trim in water is a hydrocolloid biopolymer. The linear and non-linear rheological properties of dispersions of C-trim biopolymers were investigated. The linear viscoelastic behaviours for C-trim dispersions were dependent on the β-glucan that C-trim contained. The C-trim20 and C-trim30, which have ab...