Subject to a subcritical load, a swollen polymeric gel may hesitate for a prolonged period of time without showing any macroscopic symptom, and then break suddenly. Such a phenomenon is usually referred to as the delayed fracture in gels. In this paper, we present a possible mechanism for the delayed fracture in gels from the continuum and fracture mechanics point of view. Using a continuum vis...

The aim of this study was to develop an extended-release tablet formulation using a new in situ cross-linking method. The effects of polyvalent cations on theophylline release from tablets made with the polyanionic polymers sodium alginate and sodium carboxymethylcellulose, were investigated. Different miliequivalents of the di and tri-valent cation, Ca2+ and Al3+, were added to tablet form...

The current study aimed at in vitro investigating the kinetic study and thermodynamic analysis of mebendazole drug released from electrospun cellulose nanofiber in which guar gum is used as a release controller. The nanofibers were fabricated by electrospinning technique. The fibers were boosted by different controller guar gum 10 at 50, 250, and 500 ppm concentrations. The drug releas...

the influence of various polymers on the release rate of lithium carbonate from matrix-type tablets was investigated in an attempt to formulate a sustained release solid dosage form. for this purpose, tablets containing 450 mg of lithium carbonate along with various amounts of carbopol 934p, 971p, 974p, pemulen and eudragit rlpo as retarding agents and inactive ingredients (e.g. pvp, avicel or ...

...Abstract The energy release Ls on the surface of a neutron star (NS) with a weak magnetic field and the energy release Ld in the surrounding accretion disk depend on two independent parameters that determine its state (for example, mass M and cyclic rotation frequency f) and is proportional to the accretion rate. We derive simple approximation formulas illustrating the dependence of the effi...

Background & Aims: Secondary caries is one of the most common problems in restorative dentistry. The release of flouride ions could substantially benefit the tooth enamel and neigboring dentin because flourid can combat caries. The purpose of this in vitro study was to evaluate the solubility rate and release of fluoride from tooth-colored restorative materials (Iono CID, Fuji II LC, FugiIX, Fu...

The aim of this study was to develop an extended-release tablet formulation using a new in situ cross-linking method. The effects of polyvalent cations on theophylline release from tablets made with the polyanionic polymers sodium alginate and sodium carboxymethylcellulose, were investigated. Different miliequivalents of the di and tri-valent cation, Ca2+ and Al3+, were added to tablet form...