33 resultados para Vacuum Packaging


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The electrochemistry of decamethylferrocene (DmFc) has been studied in organic solvent systems and proven to be a superior internal reference redox standard to ferrocene (Fc). However, the electrochemical information on this redox couple in ionic liquids is still limited. Therefore, the voltammetric and amperometric behaviour of DmFc was investigated under argon and vacuum conditions in six different ionic liquids and compared to that of Fc under the same experimental conditions. Consequently, the concentration, the heterogeneous electron-transfer rate constant (k0), volatility, and diffusion coefficients (D) of Fc and Fc+, as well as the solubility, k 0, and D values for DmFc and DmFc+ were determined under argon and vacuum conditions by fitting the experimental chronoamperometric and voltammetric data with numerical and digital simulations. The rate of mass transport of ferrocene and decamethylferrocene was observed to decreases between 6-37% by changing the working atmosphere from argon to vacuum. The D Fc/DFc+ ratios are in the range 1.31-2.01 in the different ILs. Importantly, the DDmFc/DDmFc+ ratio is ≈ 1 in 1-methyl-3-butylimidazolium bis(trifluoromethylsulfonyl)amide, 1-methyl-1-butylpyrrolidinium tris(pentafluoroethyl)trifluorophosphate, and 1-methyl-3-ethylimidazolium tris(pentafluoroethyl)trifluorophosphate. The experimental mid-point potential and half-wave potential of Fc0/+ vs. DmFc0/+, as well as the formal potential obtained after correction for inequality in the respective diffusion coefficients of both redox processes are presented. Even though DmFc is not freely soluble in the different ILs, the results presented in this work suggest that the DmFc0/+ redox process is less dependent than Fc on the IL nature. This is a very relevant finding for the application of this transition-metal sandwich complex as an internal reference redox system in IL solutions. © 2014 Elsevier Ltd.

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Vacuum fluidised beds have a distinct advantage of being operated with reduced mass consumption of the fluidising media. However, a low quality of fluidisation reduces the opportunity to utilise the bubbling regime in vacuum fluidised beds. Fluidisation maps are often used to depict the interface between the quiescent, bubbling and slugging regimes inside a fluidised bed. Such maps have been obtained by visual observations of the fluidisation interface in transparent fluidised beds. For beds which are visually inaccessible fluidisation maps are difficult to obtain. The present work therefore attempts to model the interface travel in a vacuum fluidised bed. The pressure gradient due to the bed weight has been determined to be a main contributor for fluidisation/defluidisation under vacuum. A simple analytical model based on the pressure gradient (PG model) is developed to predict the interface location in a vacuum fluidised bed. For a segregated bed, the Gibilaro-Rowe (GR) model is modified and used to predict the jetsam layer growth along with the fluidisation interface. The predictions are compared with the experimental data for minimally and highly segregated particles and it is seen that for non-segregated powders the predictions are quite accurate. Lack of sufficient knowledge of bubble characteristics, however, impeded accurate prediction of the jetsam growth especially at high flow rates. However, an approximate complete fluidisation interface is successfully predicted using the GR-PG model. © 2014 Elsevier B.V.

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Investigations into vacuum fluidised beds has improved understanding of heat transfer and hydrodynamics which will enable optimization of various industrial processes. Significant contributions were made in theoretical and experimental analysis.

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ABSTRACT
Background: Plain packaging (PP) with larger graphic health warnings (GHWs) was implemented in Australia in late 2012. This study examined effects of these packaging changes on short-term changes in quitting-related cognitions and behaviours.
Methods: We used a series of cohorts of Australian adult cigarette smokers originally sourced from a nationally representative cross-sectional tracking survey, followed up approximately 1 month after their baseline interview (n(weighted)=5441). Logistic regression analyses compared changes in seven quitting-related outcomes over this 1-month follow-up period for the cohorts surveyed before PP, over the period of transition to PP, and during the first year of PP, adjusting for baseline levels of the outcome and covariates.
Results: Compared to the referent group of smokers who completed their follow-up survey pre-PP, those who were followed-up in the early transition period showed greater increases in rates of stopping themselves from smoking (OR=1.51, 95% CI (1.08 to 2.10)) and higher quit attempt rates (OR=1.43, 95% CI (1.00 to 2.03)), those followed-up in the late transition period showed greater increases in intentions to quit (OR=1.42, 95% CI (1.06 to 1.92)) and pack concealment (OR=1.55, 95% CI (1.05 to 2.31)), and those followed- up in the first year of PP showed higher levels of pack concealment (OR=1.65, 95% CI (1.01 to 2.72)), more premature stubbing out of cigarettes (OR=1.55, 95% CI (1.01 to 2.36)), and higher quit attempt rates (OR=1.52, 95% CI (1.01 to 2.30)).
Conclusions: These findings provide some of the strongest evidence to date that implementation of PP with larger GHWs was associated with increased rates of quitting cognitions, microindicators of concern and quit attempts among adult cigarette smokers.

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Background: Implementation of tobacco plain packaging (PP) with larger graphic health warnings (GHWs) in Australia had positive effects on responses reflecting the specific objectives of the PP policy and on follow-up quitting-related cognitions and behaviours. The aim of this study was to examine predictive relationships bewteen these proximal and distal outcomes.
Methods: A nationally representative sample of Australian adult cigarette smokers completed a baseline survey and a 1-month follow-up survey within the first year of policy implementation (n(weighted)=3215). Logistic regression analyses tested whether baseline measures of cigarette appeal, GHW effectiveness, perceived harm and concern/enjoyment predicted each of seven follow-up measures of quitted-related cognitions and behaviours, adjusting for baseline levels of the outcome and covariates.
Results: In multivariable models, we found consistent evidence that several baseline measures of GHW effectiveness positively and significantly predicted the likelihood that smokers at follow-up reported thinking about quitting at least daily, intending to quit, having a firm date to quit, stubbing out cigarettes prematurely, stopping oneself from smoking and having attempted to quit. Two of the quitting-related outcomes were also predicted by feeling more smoking-related concern than enjoyment. A smaller number of the appeal variables were prospectively associated with quitting-related outcomes, while believing that brands do not differ in harmlessness did not positively predict any outcomes.
Conclusions: These findings provide an initial insight into the pathways through which PP with larger GHWs may lead to changes in smoking behaviour. Future research should examine whether the effects are conditional on individual demographic and smoking characteristics.

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Abstract
Background We assessed whether the Australian plain packs with larger graphic health warnings (GHWs) achieved three specific objectives of reducing the appeal of tobacco, increasing health warning effectiveness and reducing the ability of packaging to mislead about smoking harms.
Methods We compared responses from continuous cross-sectional telephone surveys of n=2176 cigarette smokers during pre-plain packaging (April–September 2012, pre-PP) with n=759 surveyed in the transition period (October–November 2012) and n=4240 during the first year of implementation (December 2012–November 2013, PP year 1), using multivariate logistic regression analyses.
Results From pre-PP to PP year 1, more smokers disliked their pack (p<0.001), perceived lower pack appeal (p<0.001), lower cigarette quality (p<0.001), lower satisfaction (p<0.001) and lower value (p<0.001) and disagreed brands differed in prestige (p=0.003). There was no change in perceived differences in taste of different brands. More smokers noticed GHWs (p<0.001), attributed much motivation to quit to GHWs (p<0.001), avoided specific GHWs when purchasing (p<0.001), and covered packs (p<0.001), with no change in perceived exaggeration of harms. PP year 1 saw an increased proportion believing that brands do not differ in harmfulness (p=0.004), but no change in the belief that variants do not differ in strength or the perceived harmfulness of cigarettes compared with a year ago. Interactions signified greater change for four outcomes assessing aspects of appeal among young adults and two appeal outcomes among mid-aged adults.
Conclusions The specific objectives of plain packaging were achieved and generally sustained among adult smokers up to 12 months after implementation.

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Objectives: To describe changes among smokers in use of various types of tobacco products, reported prices paid and cigarette consumption following the standardisation of tobacco packaging in Australia.
Methods: National cross-sectional telephone surveys of adult smokers were conducted from April 2012 (6 months before transition to plain packaging (PP) to March 2014 (15 months afterwards). Multivariable logistics regression assessed changes in products, brands and pack types/sizes; multivariable linear regression examined changes in inflation-adjusted prices paid and reported cigarette consumption between the pre-PP and three subsequent periods – the transition phase, PP year 1 and PP post-tax (post a 12.5% tax increase in December 2013).
Results: The proposition of current smokers using roll-your-own (RYO) products fluctuated over the study period. Proportions using value brands of factory-made (FM) cigarettes increased from pre-PP (21.4%) to PP year 1 (25.5%; p=0.002) and PP post-tax (27.8%; p<0.001). Inflation-adjusted prices paid increased in the PP year 1 and PP post-tax phases; the largest increases were among premium FM brands, the smallest among value brands. Consumption did not change in PP year 1 among daily, regular or current smokers declined significantly in PP post-tax (mean=14.0, SE=0.33) compared to PP year 1 (mean=14.8, SE=0.17; p=0.037).
Conclusions: Introduction of PP was associated with an increase in use of value brands, likely due to increased numbers available and smaller increases in prices for value relative to premium brands. Reported consumption declined following the December 2013 tax increase.

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This paper describes the development, content and implementation of two pieces of Australian tobacco control legislation: one to standardise the packaging of tobacco products and the other to introduce new, enlarged graphic health warnings. It describes the process of legislative drafting, public consultation and parliamentary consideration. It summarises exactly how tobacco products have been required to look since late 2012. Finally, it describes implementation, most particularly, the extent to which packs compliant with the legislation became available to consumers over time.

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ABSTRACT
Objectives: To assess whether following standardisation of tobacco packaging in Australia, smokers were, as predicted by the tobacco industry, more likely to use illicit tobacco.
Methods: National cross-sectional telephone surveys conducted continuously from April 2012 (6 months before implementation of plain packaging (PP)) to March 2014 (15 months after) using responses from current cigarette smokers (n=8679). Changes between pre-PP, the transition to PP and PP phase were examined using logistic regression models.
Results: Among those whose factory-made cigarettes were purchased in Australia, compared with pre-PP, there were no significant increases in the PP phase in use of: ‘cheap whites’ (<0.1%; OR=0.24, 95% CI 0.04 to 1.56, p=0.134); international brands purchased for 20% or more below the recommended retail price (0.2%; OR=3.49, 95% CI 0.66 to 18.35, p=0.140); or packs purchased from informal sellers (<0.1%; OR=0.24, 95% CI 0.04 to 1.47, p=0.124). The prevalence of any use of unbranded illicit tobacco remained at about 3% (adjusted OR=0.79, 95% CI 0.58 to 1.08, p=0.141).
Conclusions: While unable to quantify the total extent of use of illicit manufactured cigarettes, in this large national survey we found no evidence in Australia of increased use of two categories of manufactured cigarettes likely to be contraband, no increase in purchase from informal sellers and no increased use of unbranded illicit ‘chop-chop’ tobacco.

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