Barriers and Chemistry in a Bottle: Mechanisms in Today’s Oxygen Barriers for Tomorrow’s Materials

AbstractHybrid nanocomposites based on high-density polyethylene (HDPE)/poly (ethylene-co-vinyl alcohol) (EVOH)/clay were prepared and fully characterized. Morphological (WAXS and TEM), calorimetric (DSC), and dynamic mechanical thermal (DMTA) analyses were applied to investigate potential of nanocomposites as barrier against oxygen. Co-existence of ingredients of different nature, i.e. HDPE (general-purpose non-polar component), EVOH (engineering polar component with excellent barrier properties), nanoclay (planar one-dimensional mineral barrier nanofiller), and maleated HDPE (PE-g-MA) as coupling agent, brings about serious intricacies in view of interaction between existing phases. Conceptual/experimental analysis was performed to explore the interdependence between microstructure and oxygen barrierity of HDPE/EVOH/clay nanocomposites through the lens of interaction state in the system. Morphological measurements confirmed formation of an intercalated nanostructure, while investigations on complex viscosity, storage modulus, permeability, thermo-mechanical properties, and nanoclay interlayer galleries were all indicative of dependence of nanocomposites’ properties on molecular interactions. The performance of nanocomposite sheets as oxygen barriers was mechanistically explained.

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33.4:Distinguished Paper: Oxide Semiconductor Thin-Film Transistors Using Oxygen Barriers and a Wet-Chemical Back-Channel Etch Step

SID Symposium Digest of Technical Papers ◽

10.1002/j.2168-0159.2014.tb00124.x ◽

2014 ◽

Vol 45 (1) ◽

pp. 476-479 ◽

Cited By ~ 3

Author(s):

Marcus Herrmann ◽

Norbert Fruehauf

Keyword(s):

Thin Film ◽

Thin Film Transistors ◽

Oxide Semiconductor ◽

Wet Chemical ◽

Semiconductor Thin Film ◽

Oxygen Barriers

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Web Based Decision Support System yo Determine yhe Appropriate Packaging of Ethnic and Traditional Indonesian Foods

JITA - Journal of Information Technology and Applications (Banja Luka) - APEIRON ◽

10.7251/jit1702115n ◽

2018 ◽

Vol 14 (2) ◽

Author(s):

Latifah Nurbaiti ◽

Kudang Boro Seminar ◽

Nugraha Edhi Suyatma

Keyword(s):

Decision Support ◽

Decision Support System ◽

Support System ◽

Food Packaging ◽

Active Packaging ◽

Web Based ◽

The Right ◽

Oxygen Barriers ◽

Selection Of

Culinary efforts, especially ethnic and traditional snacks attract many people to Indonesia. Maintaining the quality of snacks for consumers requires a good packaging technique. Food packaging consists of a wide variety of packaging options that match the characteristics of each snack; this is no easy task. Decision support systems can help to facilitate decisions made regarding selection of the right packaging. This paper focuses on identifying snacks, types of packaging and active packaging parameters to build a decision support system in order to determine appropriate packaging. Types of packaging are determined using fuzzy Sugeno 4 parameters: fat, water activity, shelf-life and price. Active packaging of the snacks is done using the if-else rule with parameterised types of packaging, preservatives, oxygen barriers and water vapour barriers. The end result of this research is a web-based decision support system, which recommends types of packaging and active packaging for snacks.

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Reduction of acid generation in mine tailings through the use of moisture-retaining cover layers as oxygen barriers

Canadian Geotechnical Journal ◽

10.1139/t89-001 ◽

1989 ◽

Vol 26 (1) ◽

pp. 1-8 ◽

Cited By ~ 161

Author(s):

Ronald V. Nicholson ◽

Robert W. Gillham ◽

John A. Cherry ◽

Eric J. Reardon

Keyword(s):

Oxygen Diffusion ◽

Pyrite Oxidation ◽

Moisture Retention ◽

Gaseous Oxygen ◽

Cover Layer ◽

Fine Grained ◽

Acid Generation ◽

Tailings Remediation ◽

Diffusion Characteristics ◽

Oxygen Barriers

Acid production in sulphidic tailings can cause severe degradation of water quality in both subsurface and surface systems. The availability of gaseous oxygen and the rate of diffusion of oxygen through the open pore spaces in the upper zone of the tailings are the critical factors controlling the rate of acid generation. Acid generation can be reduced by applying a fine-grained, nonreactive cover layer to the tailings surface. The key process involves moisture retention by capillary forces so that near-saturated conditions can be maintained even when the cover layer occurs at several metres above the water table. Textured layering of fine over coarse materials improves moisture retention in the fine layer when infiltration exceeds evapotranspiration. The application of such a cover layer can theoretically reduce oxygen diffusion coefficients and rates of acid generation by up to four orders of magnitude. This can represent a substantial difference in the potential treatment costs of tailings seepage. Simplified calculations based on Fick's first law can be applied to preliminary laboratory measurements of diffusion characteristics of potential cover materials to evaluate their effectiveness in decreasing acidification. These concepts and methods provide an initial evaluation before field-scale testing of cover performance. Key words: pyrite oxidation, tailings, remediation, covers, acid generation, oxygen diffusion.

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