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691.
Cassandra D. Engeman Lynn Baumgartner Benjamin M. Carr Allison M. Fish John D. Meyerhofer Terre A. Satterfield Patricia A. Holden Barbara Herr Harthorn 《Journal of nanoparticle research》2012,14(3):749
Current research on the nanotechnology industry indicates its downstream expansion at a rapid pace, while toxicological research
and best practices for environmental health and safety are still being developed. Companies that use and/or produce engineered
nanomaterials (ENMs) have enormous potential to influence safe-handling practices for ENMs across the product life cycle.
Knowledge of both industry practices and leaders’ perceptions of risk is vital for understanding how companies will act to
control potential environmental and health risks. This article reports results from a new international survey of nanomaterials
companies in 14 countries. In this survey, company participants reported relatively high levels of uncertainty and/or perceived
risk with regard to ENMs. However, these perspectives were not accompanied by expected risk-avoidant practices or preferences
for regulatory oversight. A majority of companies indicated “lack of information” as a significant impediment to implementing
nano-specific safety practices, but they also reported practices that were inconsistent with widely available guidance. Additionally,
in the absence of safe-handling regulations, companies reported nano-specific health and safety programs that were narrow
in scope. Taken together, these findings indicate that health and safety guidance is not reaching industry. While industry
leaders’ reluctance toward regulation might be expected, their own reported unsafe practices and recognition of possible risks
suggest a more top-down approach from regulators is needed to protect workers and the environment. 相似文献
692.
693.
Establishing drying mechanisms during film formation in waterborne acrylic coatings is a technologically important problem, however complex, and still poorly understood. A model for the prediction of evaporation kinetics is proposed in this paper, where films are supposed to dry normally with respect to the film surface, and a drying front separates a top dry region from a bottom wet region. The model accounts for the competition between water evaporation and particle diffusion that determines the degree of vertical homogeneity, but also for the competition between water evaporation and particle deformation that ultimately establishes the rate-determining step in film formation processes. The model was validated by performing gravimetric water-loss experiments on latexes of acrylic polymers of various composition, various particle size and stabilizing systems, under different environmental temperatures and humidity, and various initial film thicknesses in order to evaluate the effect of the different factors that can in principle influence the film formation process. 相似文献