1. Invasions of zebra and quagga mussels have had long-term, large-scale impacts on lake ecosystems in the USA as characterised by high abundance, broad-scale spread and effective adaption to new environmental conditions. Due to their high filtering capacity, decreases in chlorophyll a (Chl) and total phosphorus (TP) concentrations have been reported in many affected lakes. 2. In 25 US lakes, w...

We demonstrate that Snell's law of refraction can be applied to thermal fronts propagating through a boundary between regions that support distinct frontal velocities. We use the free-radical frontal polymerization of a triacrylate with clay filler that allows for two domains containing two different concentrations of a peroxide initiator to be molded together. Because the polymerization reacti...

(3-(tert-butylperoxy)propyl) trimethoxysilane (TBPT), is a tailor-made new style silane coupling agent with peroxide group, which have ability of initiating polymerization. This study used TBPT to generate free radical, and initiated the polymerization of acrylonitrile (AN), thereby forming polyacrylonitrile (PAN) in two approaches, thermal initiation system and redox initiation system. Meanwhi...

OBJECTIVES Some antioxidants are believed to restore dentin bond strength after dental bleaching. This study was done to evaluate the influence of antioxidants on the bond strength of bleached bovine dentin. MATERIALS AND METHODS Thirty incisors were randomly assigned to 10 groups (two unbleached control and eight bleached groups: immediate bonding IB, 4 wk delayed bonding DB, 10% sodium asco...

the microstructure and thermal properties of the synthesized block copolymers and terpolymers via atom transfer radical polymerization (atrp) were studied. the mole fraction of the blocks and chain length of the pvac-b-pma block copolymers were estimated with 1h nmr spectroscopy.differential scanning calorimety measurement shows two different transitions at 36°c and 8°c assigned to pvac and pma...

The polymerization of 1,4-diethynylbenzene was studied on a Cu(111) surface using scanning tunneling microscopy (STM) under ultra-high vacuum conditions. Thermal activation yielded disordered covalent networks, where distinct basic structural motifs indicate different coupling reactions.