Degradation of polyamide reverse osmosis membranes in the presence of chloramine

Exposure to relatively low concentrations of chlorinated chemicals such as hypochlorite can reduce the performance and ultimately result in the failure of polyamide (PA) reverse osmosis membranes. Whereas the tolerance of PA membranes to chloramine solutions is considerably higher than that of hypochlorite, the presence of some metal ions can potentially catalyze and accelerate degradation reactions. Spectroscopic techniques are commonly used to qualitatively assess the chemical degradation of membranes by observing changes in structural peaks. This paper presents a technique to quantitatively evaluate changes in PA membranes exposed to chloramine by means of a peak ratio derived from a typical amide peak and an invariant peak in the same spectrum. The effect of some common metal ions and combinations of these on the peak ratio parameter derived from a typical amide peak is also reported

Museum pricing : challenges to theory development and practice

The museum sector has undergone considerable change in the last few decades, which has been a result of both internal and external forces. The topic of pricing in museums, however, has attracted little interest from researchers in the field despite the sector\u27s need to understand it better. This study aimed to address this gap in knowledge. Results of a comprehensive literature review on pricing highlight that the topic of pricing in museums is problematic, as a range of issues, social, political and often value-laden, must be considered before pricing decisions can be made. The study highlights that there is diversity in the sector with regard to pricing, but that museums generally adopt a unilateral approach to pricing. Researchers in entrepreneurial marketing have noted that conventional pricing theory is being turned on its head and they argue that deciding what prices to charge represents one of the more entrepreneurial strategies for organisations. This study indicates that, within the context of museums, marketers are failing to recognise and capitalise on such pricing opportunities. Approaches to setting multiple museum pricing strategies, depending on the market context, are proposed in this paper. In this way, knowledge of museum pricing can optimise the organisational outcomes of museums while continuing to meet their social responsibilities.<br /

From market failure to marketing failure: market orientation as the key to deep outreach in microfinance

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