Energy transfer has been investigated in polyvinyltoluene (PVT) scintillators containing pyrene, p-terphenyl and naphthalene by measurement of scintillation pulse shapes and yields. It is concluded that there is an initial rapid diffusion of the excitation energy with solute molecules, residual monomer and PVT excimer sites acting as competing traps. At later times energy can transfer from resi...

The purpose of this study was to investigate the amount of residual monomer in a composite resin after light-curing with different sources, light intensities and spectra of radiation. The resin specimens (4 mm in diameter; 2 mm thick) (n=5) were inserted in Plexglass matrixes and light-cured with a halogen lamp, LED and PAC units for 40, 40 and 5 s, respectively. The polymerized specimens were ...

Monomers in the polymer-based provisional crown and fixed partial denture materials form polymer network as carbon-carbon double bonds are converted to carbon-carbon single bonds during polymerization. This reaction is not complete. There will be a certain amount of monomer remaining in the resin materials. This is influenced by several factors, such as type of monomer, curing temperature, expo...

Poly(acrylamide-co-diallyldimethylammonium chloride) (PDA), which is usually prepared by free radical polymerization of acrylamide monomer (AM) onto the cationic monomer dimethyl diallyl ammonium chloride (DMDAAC), has been widely applied to wastewater treatment; however, the free-radical polymerization is always incomplete with residual AM remaining in the PDA. The residual AM affects the PDA'...

A fabrication technique for producing lightinduced self-written (LISW) waveguides for large-core optical fibers is proposed. The proposed technique employs a photopolymerizable resin consisting of two kinds of photopolymerizable monomers that differ from each other in terms of both refractive index and polymerization mechanism. The core portion is formed by virtue of a self-trapping effect, in ...

At the end of the final spin cycle of the laundry process, the residual moisture content (RMC) of fabric is directly related to the dynamic surface tension of the residual water in the fabric. The LaPlace equation for capillary rise predicts that the capillary rise of solutions in a capillary is proportional to the surface tension at the air-liquid interface. If fabric can be considered to be a...

The UNIQUAC activity coefficient model is extended to predict solid-liquid equilibrium of isotactic crystalline poly (1-butene), iPBu-1, in different organic solvents. The UNIQUAC activity coefficient model used in this work is based on the concept of group contribution and consists of combinatorial, residual and free volume terms. To account for branching of atom groups in the monomer structur...

A decoupled control law is proposed to control the concentration of monomer in the polymer particles in emulsion homopolymerization, copolymerization and terpolymerization processes and simultaneously to insure the production of a homogeneous polymer composition. Nonlinear geometric controllers are used to calculate the monomer flow rates that accomplish this purpose. The controllers are based ...

Purpose: The aim of this study is to compare the amount of Bis-GMA, UDMA, and TEGDMA released from four different types of composite resins in three different time periods using the HPLC device. Materials and Methods: Four different composite resin materials with nanofiller content were used in the study. A total of 40 sample discs were prepared and polished to provide 10 pieces for each mater...