ISSN:0894-3214    

DOI:10.1002/pts.2770070202

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractCushion curves for a moulded pulp material were constructed and compared with cushion curves for an expanded polystyrene (EPS) foam. The ability of the moulded pulp material to provide some shock absorption resulted from a number of ‘dimples’ moulded into the pulp sheet. As an impact was applied to the moulded pulp, these dimples crushed and thereby mitigated the shock. Results showed that the moulded‐pulp test samples had good cushioning characteristics for low static loadings, low drop heights, and single impacts. However, the cushioning characteristics of the material were inferior to those of EPS foam at static loadings above about 5kPa, and where higher drop heights or multiple impacts occurred. These properties were improved by using two samples with interlocking dimples. It was concluded that the material had the potential to replace EPS foam in a limited number of situations, and several recommendations for future research were

ISSN:0894-3214    

DOI:10.1002/pts.2770070203

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractA small‐scale cushion tester using small‐area test pieces was constructed primarily to evaluate the shock absorbing properties of corrugated fibreboard. Experiments were set up to compare results between the small‐area tester and a commercially available model, using samples of cross‐linked polyethylene foam from 2 to 4.2cm thick, and thus validate the results obtained with the former. A regression equation was developed to correlate the two testers. The findings indicate that there is a strong correlation between the results obtained by the two testers and that the small‐scale tester may be used when experimental design requires that the samples be exposed to extreme conditions of humidity and temperature and when there is a large number of samples of thin cushioning materials to evaluate. This paper does not suggest a replacement to commercially available testers but offers an option for handling experiments involving samples of thin cushioning materials that will be exposed to extreme environmental c

ISSN:0894-3214    

DOI:10.1002/pts.2770070204

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractCommercially prepared potato chips were packaged in laminated polymer film bags flushed with nitrogen. Head‐space oxygen concentration of nitrogen‐flushed packages was initially 0.015 atm and increased to 0.02atm after 80 days of storage at 23°C. Oxygen concentration of control packages not flushed with nitrogen remained constant at 0.2atm. Very little difference was observed in lipid oxidation rate of potato chips between the nitrogen flushed and the control packages. It seems that an oxygen concentration below 0.01 atm needs to be maintained to achieve substantial reduction in lipid oxidation rate. In spite of the little difference in lipid oxidation rate, the sensory evaluation by a trained panel showed improvement in the quality of potato chips in nitrogen flushed packages. An empirical equation obtained by Questet al. may be useful in predicting the shelf‐life of packaged potato

ISSN:0894-3214    

DOI:10.1002/pts.2770070205

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractTo measure the biodegradability of packaging materials, a scientific and methodological approach is proposed, using the results obtained with cellulosic materials as models. Their degradation was evaluated using a respirometric method based on the measurement of CO2released by microorganisms (Pseudomonas fluorescensand a mixture of cellulolytic bacteria). Our study was conducted in confined conditions, and the CO2released was detected by gas chromatography (GC). Glucose was used as a reference compound because of its complete bioassimilation by the strains studied. The percentage of carbon converted into carbon dioxide was the parameter used to classify materials according to their potential biodegradability. With both inocula, the percentage of absolute conversion of glucose to CO2reached about 36% compared with 24% and 13% for the hydrated crystalline cellulose and the paraffin waxed paper, respectively. Measurements of the percentage of absolute conversion of glucose to CO2, of the dissolved carbon in the culture medium, of the biomass carbon and of the residual glucose permitted the calculation of an approximate carbon balance withPseudomonas fluorescens. The percentages of absolute and relative conversion of packaging materials into CO2were calculated and the growth rates evaluated. It was shown that to evaluate the biodegradation of insoluble substrates, the biomass produced and the dissolved carbon must be taken into account.

ISSN:0894-3214    

DOI:10.1002/pts.2770070206

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY

ISSN:0894-3214    

DOI:10.1002/pts.2770070207

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY

ISSN:0894-3214    

DOI:10.1002/pts.2770070209

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY

ISSN:0894-3214    

DOI:10.1002/pts.2770070210

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY

ISSN:0894-3214    

DOI:10.1002/pts.2770070211

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY

ISSN:0894-3214    

DOI:10.1002/pts.2770070201

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY