Standard Formaldehyde Source for Chamber Testing of Material Emissions: Model Development, Experimental Evaluation, and Impacts of Environmental Factors

Formaldehyde, which is recognized as a harmful indoor air pollutant for human health, is emitted mainly from urea-formaldehyde resin in wood products. Chamber tests are used to evaluate formaldehyde emission rates from these products. However, there is no available formaldehyde standard reference emission source to assess the performance of chamber testing systems. In this work, a LIFE (liquid-inner tube diffusion-film-emission) formaldehyde reference is described. The formaldehyde source consists of a polytetrafluoroethene (PTFE) tube that holds a formaldehyde–water solution with a concentration of 16 g formaldehyde per 100 mL water, with a thin polydimethylsiloxane (PDMS) film cover. Formaldehyde emission parameters for the PDMS film (diffusion coefficient and partition coefficient) were determined experimentally, thereby enabling the prediction of the formaldehyde emissions from the source for use as a reference value in a chamber. Chamber tests were conducted in a 51 L stainless steel ventilated chamber. The impacts of temperature and relative humidity on the emissions were investigated. Results show the LIFE’s chamber test results match those predicted by a mass transfer model. As a result, this formaldehyde source may be used to generate a reference concentration in product emission testing chambers, thereby providing a powerful tool to evaluate the performance of the chamber testing systems

Impact of Brand Equity on Customer Acquisition, Retention, and Profit Margin

This paper examines the relationship between brand equity and customer acquisition, retention, and profit margin, the key components of customer lifetime value (CLV). We examine a unique database from the U.S. automobile market that combines 10 years of acquisition rate, retention rate, and customer profitability data with measures of brand equity from Young & Rubicam’s Brand Asset Valuator (BAV) over the same time period. We hypothesize and find that BAV brand equity is significantly associated with the components of CLV in expected and meaningful ways. For example, customer Knowledge of a brand has an especially strong positive relationship with all three components of CLV. Interestingly, however, Differentiation is a double-edged sword. While it is associated with higher customer profitability, it is also associated with lower acquisition and retention rates. We also find that marketing efforts exert indirect impacts on CLV through brand equity. Simulations show that changes in marketing, or exogenous changes in brand equity, can exert important effects on CLV. Overall, the findings suggest the “soft” and “hard” sides of marketing need to be managed in a coordinated fashion. We discuss these and other implications for researchers and practitioners