Diffusion of linalool and methylchavicol from polyethylene-based antimicrobial packaging films

The diffusion of linalool and methylchavicol from thin (45–50 μm) antimicrobial low-density polyethylene-based films was evaluated after immersion in isooctane and the effect of temperature (4, 10, or 25 °C) on the diffusion rate was evaluated. The kinetics of linalool and methylchavicol release showed a non-Fickian behavior at the lowest temperature. An increase in temperature from 4 °C to 25 °C resulted in an increase in the diffusion coefficient from 4.2 × 10−13 m2 s−1 to 2.5 × 10−12 m2 s−1 for linalool and from 3.5 × 10−13 m2 s−1 to 1.1 × 10−12 m2 s−1 for methylchavicol. The effect of temperature on the diffusion coefficient followed an Arrhenius-type model (r2 = 0.972) in relation to a time-response function with a Hill coefficient. Activation energies of 57.8 kJ mol−1 (linalool) and 42.8 kJ mol−1 (methylchavicol) were observed

Review Article: Anthropology and the Biblical Exile

Over the past three decades there have been a few attempts to use social anthropology to explore the Old Testament (OT) and interdisciplinary studies of this sort are now becoming more mainstream. Historical and archaeological data concerning ancient societies are necessarily limited in scope, and anthropological comparisons may offer insights into historical peoples who cannot be observed. This article discusses recent trends in post-exilic studies, in particular those appealing to anthropology

A mathematical model for the sequestering of chemical contaminants by magnetic particles

A mathematical model is developed and implemented to characterize the pickup of various liquid chemical contaminants by polyethylene-coated magnetic particles. The model and its associated experimental and analytical protocols were applied to a wide range of liquid chemicals in order to gain insights into the physical basis for the pickup phenomenon. The characteristics of the pickup isotherms range between “ideal” and “nonideal” behaviors that are reflected in the mathematical model by a single parameter, �0, where �0=1 corresponds to ideal behavior and �0�1 corresponds to a departure from idealized behavior that is directly quantified by the magnitude of �0. The parameter �0 is also related to the efficiency of pickup, and since most isotherms observed in the study deviate from ideality, the high efficiency of pickup observed in these systems has been attributed in part to this deviation. The proposed model and its associated experimental and analytical protocols demonstrate great potential for the systematic evaluation of the uptake of chemical contaminants using magnetic particle technology

Antimicrobial Activity of Biodegradable Polysaccharide and Protein-Based Films Containing Active Agents

Significant interest has emerged in the introduction of food packaging materials manufactured from biodegradable polymers that have the potential to reduce the environmental impacts associated with conventional packaging materials. Current technologies in active packaging enable effective antimicrobial (AM) packaging films to be prepared from biodegradable materials that have been modified and/or blended with different compatible materials and/or plasticisers. A wide range of AM films prepared from modified biodegradable materials have the potential to be used for packaging of various food products. This review examines biodegradable polymers derived from polysaccharides and protein-based materials for their potential use in packaging systems designed for the protection of food products from microbial contamination. A comprehensive table that systematically analyses and categorizes much of the current literature in this area is included in the review

Reinforcement of refined and semi-refined carrageenan film with nanocellulose

Carrageenans obtained from seaweeds can be processed into films for a range of applications including food packaging. The level of carrageenan refinement during extraction can influence the key properties, with semi-refined carrageenan (SRC) containing more impurities than the more refined carrageenan (RC). Further refinement steps, however, result in higher costs associated with the production of RC. In order to obtain a lower cost and more ecofriendly, bio-based material for food packaging applications, SRC was used in this investigation to produce a thin film reinforced with nanocellulose fibrils (NCF). Films derived from RC containing NCF were also investigated with water sensitivity and physico-mechanical and thermal properties among the properties tested. Levels of NCF were varied from 1% to 7% (w/w), and in general, the NCF reinforcement improved the overall properties of both the SRC and RC films, including the water sensitivity and moisture barrier. However, NCF inclusion in SRC film was less effective with regard to the mechanical and thermal properties compared with NCF inclusion in RC film. The enhancement in properties was attributed to the greater cohesiveness of the reinforced polymer structure and the crystalline regions formed in the structures of SRC and RC films by NCF incorporation