This work on the etching of polymers in oxygen plasmas begins with a general review of experimental data and modeling attempts. Result analysis leads to an extended etching model based on the description of polymer surfaces composed of chain segments randomly distributed and taking into account the microscopic structure of polymers at the atomic and molecular level. Experimental data also suggest that thermally activated desorption of CO, in addition to CO 2 desorption, and UV-induced etching, in addition to ion-induced etching, must be incorporated in the modeling. The analytical results confirm the impossibility to reach perfect anisotropy in presence of UVinduced desorption and also to determine directly from Arrhenius plots the activation energies for CO and CO 2 thermal desorption.

Siraitia grosvenorii fruit extract capped AuNPs exhibited excellent catalytic activity in the reduction of nitrophenols and high sensitivity and selectivity for detection of Pb(ii) ions.

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Ever-increasing both data speed and traffic volume in the network telecommunications; as a result, producing more heat loss, challenges the conventional cooling methods. An optical plug module is a transceiver in data communication applications. By increasing the cooling demands, new thermal management solutions are necessary for optical plug modules. This article experimentally studies the heat pipe based cooling solutions for the optical plug modules. Heat pipes can passively transfer part of the produced heat from the hardly accessible places of the modules and expose it to the present active air cooling. Three different heat pipe based arrangements for a four-port optical plug assembly at both free and forced convection were investigated. Based on the results heat pipes helped to reduce heat sinks and total thermal resistance of this assembly on average by 27% and 16%, respectively under airflow rate of 10 ft3/min.

This study examines market reactions to firms with different level of R&D expenditure. In particular, we investigate whether R&D investment in an uncertain environment, such as during the global financial crisis of 2008, will aggravate the level of information asymmetry and increase the likelihood of undervaluation on R&D stocks. We use a sample of Taiwanese firms and classify the sample into four portfolios: no R&D, low R&D, middle R&D and high R&D firms, and estimate abnormal returns using the Fama and French three factor and Carhart four factor models. We find that the no R&D portfolio has the highest positive and significant abnormal returns in the non-crisis period (2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007), while the high R&D portfolio has the highest abnormal return in crisis period (2008)(2009)(2010)(2011). Our multivariate analysis provides supporting evidence that high R&D firms have a greater extent of information asymmetry than no R&D firms during the crisis period, while no R&D firms bear a high risk of low growth potential in non-crisis period. Similar results are obtained either by equal-weighted or value-weighted portfolio returns. Recent studies propose that investors may misprice high-tech firms. Our results provide international evidence that investors react differently to no R&D and R&D intensive firms, and R&D investment in crisis period will aggravate information asymmetry and the extent to which investors underestimate the value of R&D stocks.

The objective in Part II is to verify whether the model developed in Part I for the etching of polymers in oxygen plasmas can apply to all types of polymers. The experimental parametric study of the etching of different polymers in oxygen plasmas and under distinct operating conditions confirms that their etching kinetics follow the general laws derived from the modeling: 1) under identical operating conditions, the etch rates of polymer films with equal carbon concentration are the same and 2) the activation energies for spontaneous etching are shown to be effectively independent of the plasma operating conditions, and their values, common to all polymers, are 0.76 ± 0.05 eV for CO 2 desorption and 0.40 ± 0.05 eV for CO desorption.