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 formulat...

this paper introduces an innovative partially destructive method, called “twist-off”, for the assessment of in situ concrete strength. in this method a 40mm diameter metal probe is bonded to a concrete surface by means of a high strength epoxy resin adhesive. to measure the concrete compressive strength, a torque is applied using an ordinary torque-meter and the maximum shear stress at failure ...

abstract with increasing population, mine activities for metal proceeding are also increasing, so environment will be influenced by contaminant especially heavy metals. in situ immobilization of heavy metals using inexpensive amendments is considered as a simple and cost-effective approach for reducing heavy metal contamination. in this research we used sequential extraction for assessing reduc...

This paper reports a novel method for in-situ formation of hydrogel membranes and geometrically controlled selfassembly of colloidal crystals in microchannels using one step stamping. The simple elastomeric stamp was made of PDMS from SU-8 patterned master using standard soft lithography. Then the selective hydrophobic pattern on the PDMS stamp surface was achieved using Pluronic F127 coating a...

Dissolution stability over the entire shelf life duration is of critical importance to ensure the quality of solid dosage forms. Changes in the drug release profile during storage may affect the bioavailability of drug products. This study investigated the stability of a commercial tablet (Lescolr XL) when stored under accelerated conditions (40 oC/75% r.h.). Terahertz pulsed imaging (TPI) was ...

In order to form model aluminide coatings for studying critical issues related to their high temperature oxidation and corrosion performance, a laboratory chemical vapor deposition (CVD) procedure is being used to more rigorously control the coating process in terms of composition, purity and microstructure. One ferritic (Fe-9Cr1Mo) and one austenitic alloy (304L) were selected as substrate mat...

Trace metals, especially copper, are commonly occurring contaminants in harbors and marinas. One source of copper to these environs is copper-based antifouling coatings used on vessel hulls. The objective of this study was to measure dissolved copper contributions from recreational vessel antifouling coatings for both passive leaching and hull cleaning activities. To accomplish this goal, three...

Two quaternary ammonium silanes (QAS) were used to coat silicone rubber tracheoesophageal shunt prostheses, yielding a positively charged surface. One QAS coating [(trimethoxysilyl)-propyldimethyloctadecylammonium chloride] was applied through chemical bonding, while the other coating, Biocidal ZF, was sprayed onto the silicone rubber surface. The sprayed coating lost its stability within an ho...

Film coating of fine particles (5-20 microns) by polymers has a wide range of industrial applications, yet few techniques are commercially available that are environmentally friendly. In this study, four different techniques are considered with an ultimate goal of developing a reliable technique that is scaleable and is also environmentally friendly. Two of these techniques are fluidization bas...