BACKGROUND Amines in epoxy hardeners are significant causes of occupational allergic contact dermatitis among workers who use epoxy resin systems. OBJECTIVES To describe a novel group of contact allergens: N-(2-phenylethyl) derivatives of the reactive amine 1,3-benzenedimethanamine (1,3-BDMA). METHODS We describe the clinical examinations and exposure of 6 patients with occupational contact...

We describe a new approach to modelling pearlescent paints based on decomposing paint layers into stacks of imaginary thin sublayers. The sublayers are chosen so thin that multiple scattering can be considered across different sublayers, while it can be neglected within each of the sublayers. Based on this assumption, an efficient recursive procedure of assembling the layers is developed, which...

The objectives in this study were to deterrnine the through-thickness elastic constant of fiber-epoxy/metal composites with ultrasonic measurements and determine the elastic constants of the constituent layers. The specimens that we studied consist of alternaring layers of aluminum (2024 TI) and fiber-epoxy [1], all of which are 200 to 300 jlm thick. As Figure 1 indicates the outer two layers o...

The graphene nanosheets-based epoxy resin coating (0, 0.1, 0.4 and 0.7 wt %) was prepared by a situ-synthesis method. The effect of polyvinylpyrrolidone/reduced graphene oxide (PVP-rGO) on mechanical and thermal properties of epoxy resin coating was investigated using nanoindentation technique and thermogravimetric analysis, respectively. A significant enhancement (ca. 213% and 73 °C) in the Yo...

The effects of amine functionalization of carbon nanotubes (CNTs) and CNTs weight percent (wt. %), on the first bending natural frequencies and damping properties of CNT/epoxy composites are investigated in this paper. CNTs and amine functionalized CNTs (AFCNTs), with two different weight percentages, are used to manufacture the beam shaped specimens. Epoxy, CNT/epoxy (0.25 and 0.5 wt. % of CNT...

In this study we estimated the number of housing units in the United States with lead-based paint and lead-based paint hazards. We included measurements of lead in intact and deteriorated paint, interior dust, and bare soil. A nationally representative, random sample of 831 housing units was evaluated in a survey between 1998 and 2000; the units and their occupants did not differ significantly ...

A polychlorinated biphenyl (PCB) that was not produced as part of the Aroclor mixtures banned in the 1980s was recently reported in air samples collected in Chicago, Philadelphia, the Arctic, and several sites around the Great Lakes. In Chicago, the congener 3,3'-dichlorobiphenyl or PCB11 was found to be the fifth most concentrated congener and ubiquitous throughout the city. The congener exhib...

Recent advances in paint technology have guided the development of novel “ready-to-use” paint formulations in which microencapsulated insecticides, or active ingredients (AIs), are embedded in the paint matrix and gradually released on the surface of the dried paint [1]. It is argued that the slow-release mechanisms enable uniform AI surface concentrations with prolonged residual effect, as com...

The incorporation of a commercially available coprecipitant into the AMPLICOR enterovirus PCR test specimen preparation enhanced the sensitivity and reproducibility of this assay. Fifty-five previously tested archived cerebrospinal fluids (CSF) specimens were tested in a blind study in duplicate with and without Pellet Paint coprecipitant (Novagen, Inc., Madison, Wis.). Of these specimens, 26 h...

In situ imaging nanoindentation was used to characterize the mechanical properties of pure paint films on eight types of plywood-based flooring with different wear resistance. Correlation between the mechanical properties of paint films and the wear resistance of wood-based floorings was investigated. The average modulus of elasticity (MOE) and hardness of the paint film tested were 3.33–5.77 a...