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Graphical abstract Abstract A series of pilot-scale pool test fires simulated an idealized fire accident in a storage tank containing low-sulfur No. 6 heavy fuel oil (LSFO6). This work demonstrates that the combustion characteristics of LSFO6 and shows that fire-related emission factors (EFs) of 16 USEPA PAHs during pool fires very much depend on the scale of oil pan diameter (D). Over the range studied (D = 20–60 cm), the combustion characteristics, (i) fuel mass loss rate, (ii) heat flux and (iii) ratio of CO/CO 2 as time-weighted averages have positive linear relationships with D , but the combustion efficiency is a negative linear function of D. The sum of 16 PAH EFs has a negative linear function of D , while the overall vapor-particulate partitioning coefficient of 16 PAHs has a positive linear function of D. Most benzo(a)pyrene-toxic equivalents (BaPeq) for a given pool scale arise from high-molecular-weight PAHs. However, the maximum total BaPeq occurs at pool fire scale of D = 40 cm. The scale of burning causes no significant variation in PAH source identifications in terms of the defined molecular diagnostic ratios. Further researches on large-scale pool test fires are needed to validate whether the applicability of pilot-scale studies will be acceptable to the relevant oil tank fires in industries. [ABSTRACT FROM AUTHOR]

Kinetic analysis for the formation of acrylamide in heated foods has been typically performed using only measured data of acrylamide in foods; however, its possible loss caused by release from heated foods into fried oil and air has seldom been considered. The results obtained from the monitoring of acrylamide by frying French fries indicated that acrylamide is distributed in three phases: French fries, frying oil, and air. From the evolved gas analysis of acrylamide and the measured concentration profile of the total acrylamide amount present in these phases, the kinetic behaviour for acrylamide formation does not obey the commonly used model of two-step consecutive reactions during frying, while a lumped kinetic model was proposed for the total acrylamide amount. Moreover, a high acrylamide level in air was observed, implying that, apart from consumers of French fries, fast-food restaurant workers are potentially subject to occupational hazards from acrylamide inhalation. [ABSTRACT FROM AUTHOR]

Abstract: A real-time quartz crystal microbalance (QCM) technique was employed to monitor early formation of Pseudomonas fluorescens biofilms. To better understand the dynamic process of conditioning film and early biofilm formation, all experiments were conducted in a laminar flow-through chamber under various environmental conditions. Prior to early biofilm formation, a conditioning film comprising organic, inorganic and macromolecular substances was detected over the sensor chip surface within an extremely short duration due to their instantaneous adsorption. Based on atomic force microscopy (AFM) observations, we identified different surface features associated with various conditioning films, demonstrating that the sensor chip surface displayed complex properties in terms of surface topography, roughness, water contact angle, and conditioning film chemistry. There appeared to be a lag time before early biofilm formation. The rate of early biofilm formation was found to differ considerably, depending upon the characteristics of conditioning films and environmental conditions. However, subsequent biofilm formation could be mediated by environmental conditions, reflecting the complex and dynamic process of biofilm development. Of particular interest was the direct in situ real-time observation of the overall sequence of biofilm development processes using a QCM, starting with conditioning film formation, followed by initial bacterial adhesion and subsequently by biofilm formation. [ABSTRACT FROM AUTHOR]