The aim of this work was to evaluate the thermo-physiological comfort and moisture properties of surgical cotton gauze coated with chitosan (CH). Gauze was coated with CH at mass fractions of 0.5, ...0.25, 0.125, 0.1, 0.063 wt%. Thermal, moisture management and morphological properties were evaluated. Results indicate that the functionalized medical gauze induces low capilarity, allowing a good degree of moisture and absorption capacity of wound exudates. This biofunctional medical gauze coated with CH0,125 wt% demonstrates to deliver an efficient coating and promote the best conditions for maintenance of the wound microenvironment.
AbstractIn order to study the feasibility of the rehabilitation of the building of the Palace of Riva Herrera (sixteenth century), in Santander, Spain, four types of natural stone found in the ...building have been characterized. The chemical, microstructural, physical, and mechanical properties have been obtained. Also, in order to evaluate the durability of the stones, a program of freeze-thaw aging has been completed. In parallel, the effect of four commercial water repellents and consolidants was analyzed by means of capillary absorption tests. The results showed relations between the durability and the open porosity of the different stones. The capillarity absorption coefficient can be applied as an indicator of durability. Also, all of the waterproofing treatments were shown to be effective, reducing the capillary absorption of the treated stones with respect to the stones not subjected to protective treatments by virtue of a delay in the capillarity process, this effect being greater in more porous material.
Si la détermination de l'angle de contact d'équilibre d'une interface entre fluides rejoignant une surface solide homogène est une question comprise depuis fort longtemps, il est loin d'en être de ...même pour la dynamique de cette ligne. On propose de représenter cette dynamique par une relation de mobilité de type Onsager entre vitesse et déviation de l'angle de contact par rapport à sa valeur d'équilibre. Lorsque ce déplacement est dû à une évaporation/condensation locale, s'introduit un facteur cinétique d'Arrhenius qui peut être suffisamment petit pour que la mobilité de la ligne soit effectivement le facteur limitant dans de nombreux cas physiques. Alors, la forme de l'interface liquide/vapeur en quasi-équilibre donnera une valeur de l'angle de contact et finalement la vitesse de la ligne.
Although the contact angle at equilibrium has a well understood theory for the case of flat homogeneous solid surfaces, the displacement of the contact line is still not well understood. We propose to introduce in the dynamics of the contact line a mobility relation between the deviation of the contact angle out of its equilibrium value and the speed of the line on the solid. When the line slides on the solid thanks to an evaporation/condensation process, this introduces a dynamical Arrhenius factor that may be sufficiently small to make the mobility of the contact line the limiting factor of the dynamics in many physical situations. Then, the shape of the liquid/vapor interface will be in quasi equilibrium giving a contact angle that will define ultimately the speed of the contact line.
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