ISSN:0894-3214    

DOI:10.1002/pts.2770030202

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY

ISSN:0894-3214    

DOI:10.1002/pts.2770030203

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY

摘要:

AbstractThe experiments reported here have studied the following systems within the temperature range 25–50°C: sorption and desorption of solvents on LDPE, OPP, PS, rigid PVC, OPA, PETP and regenerated cellulose with methanol, ethanol,n‐propanol, and ethyl acetate. With reference to these, the theory presented indicates the most important aspects related to the tests, refers to identification data on similar problems and enumerates the possibilities of interaction.The application of equation 1 and the reported measuring method allows the determination of diffusion coefficients within a vapour‐saturated atmosphere system. As the gravimetric method also allows the determination of solubilities (αL, the solubility coefficient), the permeation behaviour in the Fick range is calculable from\documentclass{article}\pagestyle{empty}\begin{document}$$ P = D.\alpha _L $$\end{document}The equation used by the author can be related to other equations from the technical literature, such as\documentclass{article}\pagestyle{empty}\begin{document}$$ \frac{{Q_{(t)} }}{{Q(\infty)}} = 1 - \frac{8}{{\pi ^2 }}.e^{ - D.\pi ^{2.} .t/L^2 } $$\end{document}for the range Q(t)Q∞>0.4, or where\documentclass{article}\pagestyle{empty}\begin{document}$$ \frac{{Q_{(t)} }}{{Q(\infty)}} = \sqrt {\frac{{16.D.t}}{{\pi .L^2 }}} $$\end{document}for the range<0.4The agreement can be considered as good. TheDvalues provide a calculation base within the scope of the outlined problem definition.The taste limits for solvents in water reveal which solvents could, as residual solvents, become critical. These values—connected with sorption/desorption identification values, evaporation numbers etc. —indicate where there is a risk and those cases where sufficient drying, or even the use of more adequate solvents

ISSN:0894-3214    

DOI:10.1002/pts.2770030204

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY

摘要:

AbstractThe purpose of this study was to simulate transport vibrations and to develop a technique to evaluate the performance of chemical tanks that had been approved by existing US Department of Transportation test methods. The containers tested were six different types of portable tanks used to ship chemicals. The tanks had a capacity of 250–300 gallons (USA) and contained liquids with a specific gravity of 1.1–1.2. Fractures were seen in some of these tanks as a result of transportation. These were attributed to high vibration magnification factors developed during transport by truck. The bottom panels were stiffened by providing added thickness to the plate and also by welding the elbow to the bottom plate. This reduced the magnification factors and increased trip l

ISSN:0894-3214    

DOI:10.1002/pts.2770030205

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY

摘要:

AbstractIn two different ‘cook‐in‐the‐bag’ ham products packed in polyamide‐ethylene ionomer laminate pouches, the same obtrusive catty off‐odour was complained about. In this paper the analytical resolution of a complex off‐odour problem is described. Identification of the catty odour as the mesityf oxide‐hydrogen sulphide adduct 4‐methyl‐4‐mercaptopentan‐2‐one is followed by investigating the formation of the off‐odour with the aid of different model experiments. It is pointed out that the ethylene ionomer material that is used for the sealing layer of the multilayer packaging film has some dehydration property for diacetone alcohol, which was found as a residual solvent in the film material in question. Probably this pathway seems most likely to be

ISSN:0894-3214    

DOI:10.1002/pts.2770030206

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY

摘要:

AbstractThe influence of B‐ionizing radiation on chemical structure and mass transfer phenomena was studied in the principal flexible food packaging materials (LDPE and OPP). No significant changes were observed in the structure of polymer matrices or in oxygen permeability and global migration after ionizing the materials at dose levels approved for food products (<110 kGy). Nevertheless, at low doses, it was observed that volatile organic compounds were present in ionized films. Several oxidation products were analysed by a dynamic head space technique. These oxidation products (typically ketones, aldehydes and carboxylic acids) could play a part in the organoleptic properties of prepackaged foods and, consequently, in their shelf‐l

ISSN:0894-3214    

DOI:10.1002/pts.2770030207

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY

摘要:

AbstractManufacturers of closed‐cell cushioning materials traditionally publish cushion curves for a given material only for a limited number of impacts. The goal of this research was to describe the change in the cell structure of a close‐cell foam due to multiple impacts, and to extend the range of application of these cushion curves as they relate to reusable packaging. Cushion curves and stress‐strain curves for up to 15 compressions were generated for three different molded closed‐cell foams. The cushion curves demonstrate a constant increase in the shock transmitted with each impact due to significant permanent deformation in the form of cell‐wall fatigue and rupture. The results also show that although the mean percentage increase in transmitted shock was greatest from the first impact to the fifth impact, the change continued to be significant with subsequen

ISSN:0894-3214    

DOI:10.1002/pts.2770030208

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY

ISSN:0894-3214    

DOI:10.1002/pts.2770030209

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY

ISSN:0894-3214    

DOI:10.1002/pts.2770030210

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY

ISSN:0894-3214    

DOI:10.1002/pts.2770030201

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY