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The purpose of this paper is to evaluate the fire resistance of an innovative carbon-reinforced PEKK composite for aeronautical applications. To this end, thermal degradation analysis under inert and oxidative atmosphere is carried out. Moreover, a linear model fitting approach is compared to a generally used isoconversional method to validate its reliability for kinetic triplet estimation.

Thermogravimetric analysis carried out under inert and oxidative atmospheres, between 25 and 1000°C for three different heating rates (5, 15, 25°C/min), followed by a qualitative SEM observation of the samples before and after thermal treatment. After the reaction identification by TG/DTG curves, an isoconversional analysis is carried out to estimate the activation energy as a function of the reaction conversion rate. For the identified reactions, the kinetic triplet is estimated by different methods and the results are compared to evaluate their reliability.

In inert case, one global reaction, observed between 500-700°C, seems able to describe the degradation of carbon-PEKK resin. Under oxidative atmosphere, three main reactions are identified, besides the resin degradation, the other two are attributed to char and fiber oxidation. Good agreement achieved between isoconversional and linear model fitting methods in activation energy calculation. The achieved results demonstrate the high thermal resistance of PEKK associated with the ether and ketone bonds between the three aromatic groups of its monomer.

This paper provides a possible degradation model useful for numerical implementation in CFD calculations for aircraft components design, when exposed to high temperatures and fire conditions.

Although the use of instant messaging (IM) at work has been studied in the IS field, its effective use and impact on performance have not been adequately addressed. The purpose of this paper is to explore the antecedents and consequences of the effective use of IM at work by adapting Burton-Jones and Grange’s theory of effective use.

The authors introduce “Comprehensive IM policy” as a facilitator of adaptation and learning actions to improve the effective use of IM, which will improve communication quality and productivity. The impact of IM competence on effective use is also discussed. Based on a survey of 215 managers, this study applies the partial least square technique to test the research model.

The results indicate that comprehensive IM policy encourages adaptation and learning actions, which improve the effective use of IM and thereafter improve communication quality and productivity. Meanwhile, IM competence has a substitutive interaction effect with IM reconfiguration and self-learning on effective use.

The results refine the general theory of effective use and provide managers with an approach to leverage IM use at work for performance gains.

Innovative use of enterprise systems (ES) by employees is essential for organisations to benefit from huge investments in such systems. Drawing on job demands-resources (JDR) theory, this study explores how stressors (i.e. challenge and hindrance stressors) influence employees' innovative use of ES, as well as considering the moderating effects of IT mindfulness.

Data were collected from a longitudinal survey of 152 employees in a large financial service company in China. Hierarchical multiple regression was used to test the research model.

Results showed that challenge stressors exerted a positive effect and hindrance stressors had no significant effect on innovative use of ES. Furthermore, we found that IT mindfulness weakened the positive effect of challenge stressors and the negative effect of hindrance stressors on innovative use of ES.

This study is among the first to extend the research of innovative use of ES by considering two types of stressors based on the JDR theory. Besides, new insights are provided on how to promote employees' innovative use of ES in the post-acceptance stage according to the different levels of IT mindfulness of employees.

The following is an introductory profile of the fastest growing firms over the three-year period of the study listed by corporate reputation ranking order. The business activities in which the firms are engaged are outlined to provide background information for the reader.

The study concentrates on the shift in maintenance philosophy and on the factors raising the “value” of maintenance in “corporate thinking”.

In the ‘old days’, throughout the 1970s and early 1980s, the adage in the IT industry used to be ‘Nobody ever gets fired for buying IBM’. IBM would sell complete solutions, hardware and software (operating systems and applications) to meet all needs. These days it is more likely to be ‘Nobody ever gets fired for buying Microsoft’. Microsoft do not sell complete solutions. The only hardware they currently sell are ergonomic keyboards, mice and game accessories. Their dominance comes solely from their software.

The Board of Agriculture, by virtue of the powers conferred upon them by the Sale of Food and Drugs Act, 1899, have made regulations whereby it may be presumed, until the contrary is proved, that milk containing less than 8·5 per cent. of solids‐not‐fat, or less than 3 per cent of fat, is adulterated within the meaning of the Act. The suggested limit for fat in milk recommended by the special committee appointed by the Board of Agriculture was 3·per cent., and it will therefore be observed that the new regulations have fixed a standard for milk‐fat which is even lower than the low limit recommended by the committee. There are even rumours that a further lowering of this standard is to bo urged upon the authorities. Although from the point of view of Public Analysts and the officials responsible for the enforcement of the Food and Drugs Acts it is satisfactory that an official standard for the composition of milk has at last been set up, it is idle to suppose that the fixing of such a limit will materially improve the character of the milk‐supply as a whole. It should be remembered that milk which contains only 3 per cent of fat, although under the new regulations legally “genuine,” is, as a matter of fact, of the poorest quality, and is only produced by a cow when in bad condition, or by a particular breed of cow which is remarkable more for the quantity than for the quality of the fluid yielded. Producers and vendors of milk of good quality have been placed in a very unfortunate position by the new regulations, as the tendency of the trade will be to lower all milk to the official limits, with the result that those dealers who are still desirous of maintaining a high standard of quality will have to compete in the matter of price with less conscientious traders, who, taking advantage of the protection afforded by the regulations, will be enabled to sell to the public “genuine” milk, from which all “superfluous” fat has been removed. Gradation of quality in an article of food cannot, of course, be provided for by official regulation, and for the purpose of legal classification it is only possible to differentiate between legally “genuine” and adulterated articles. Therefore, in a legal sense, and also in a popular sense, a milk containing 4 per cent. of fat is no more “ genuine ” than one containing 3 per cent., although the former is, of course, a superior article. Competition in the dairy trade, which has of late years become very keen, will, as the result of the fixing of this standard, become more acute than before, and to keep their position it will be necessary for those milk‐vendors who are desirous of maintaining their reputation as vendors of milk of good quality to give to their customers some guarantee that their product is indeed superior to the legalised article. Any statements of the traders themselves upon this point will naturally be received by customers with reserve, as proceeding from an interested source, and the guarantee, to be effective, must therefore be given by an authority whose statements are above suspicion. It is hero that the system of Control will be found to be a necessity both to the milk dealer and milk consumer.