Novel Module-Based Membrane Reactor Design Approach for Improved Operability Performance.

This work aims to address the design and control challenges caused by the integration of phenomena and the loss of degrees of freedom (DOF) that occur in the intensification of membrane reactor units. First, a novel approach to designing membrane reactor units is proposed. This approach consists of designing smaller modules based on specific phenomena such as heat exchange, reactions, and mass transport and combining them in series to produce the final modular membrane-based unit. This approach to designing membrane reactors is then assessed using a process operability analysis for the first time to maximize the operability index, as a way of quantifying the operational performance of intensified processes. This work demonstrates that by designing membrane reactors in this way, the operability of the original membrane reactor design can be significantly improved, translating to an improvement in achievability for a potential control structure implementation.

And She's Buying a Stairway to Health: Signs and Participant Factors Influencing Stair Ascent at a Public Airport.

Several studies have demonstrated that point-of-choice prompts modestly increase stair use (i.e., incidental physical activity) in many public places, but evidence of effectiveness in airport settings is weak. Furthermore, evaluating the effects of past physical activity on stair use and on point-of-choice prompts to increase stair use is lacking. The purpose of this study was to evaluate the influence of sign prompts and participant factors including past physical activity on stair ascent in an airport setting. We used a quasi-experimental design, systematically introducing and removing sign prompts daily across 22 days at the San Diego International Airport. Intercept interviewers recruited stair and escalator ascenders (N = 1091; 33.0% interview refusal rate) of the only stairs/escalators providing access to Terminal 1 from the parking lot. A 13-item questionnaire about demographics, physical activity, health behavior, and contextual factors provided data not available in nearly all other stair use studies. We examined the effects of signs and self-reported covariates using multivariable logistic regression analyses, and tested whether physical activity and other covariates modified the intervention effect. Adjusting for all significant covariates, prompts increased the odds of stair use (odds ratio 3.67; p < .001). Past participation in vigorous physical activity increased the odds of stair use by 1.62 (p = 0.001). None of the covariates moderated the intervention effect. In conclusion, vigorous physical activity and correlates of physical activity were related to stair use in expected directions, but did not modify the effect of the intervention. This indicates that the effects of point-of-choice prompts are independent of past physical activity, making them effective interventions for active adults and the higher risk population of inactive adults. Signs can prompt stair use in an airport setting and might be employed at most public stairs to increase rates of incidental physical activity and contribute to overall improvements in population health.