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Abstract Leaf energy balance may influence plant performance and community composition. While biophysical theory can link leaf energy balance to many traits and environment variables, predicting leaf temperature and key driver traits with incomplete parameterizations remains challenging. Predicting thermal offsets (δ,Tleaf − Tairdifference) or thermal coupling strengths (β,Tleafvs.Tairslope) is challenging.We ask: (a) whether environmental gradients predict variation in energy balance traits (absorptance, leaf angle, stomatal distribution, maximum stomatal conductance, leaf area, leaf height); (b) whether commonly measured leaf functional traits (dry matter content, mass per area, nitrogen fraction, δ13C, height above ground) predict energy balance traits; and (c) how traits and environmental variables predictδandβamong species.We address these questions with diurnal measurements of 41 species co‐occurring along a 1,100 m elevation gradient spanning desert to alpine biomes. We show that (a) energy balance traits are only weakly associated with environmental gradients and (b) are not well predicted by common functional traits. We also show that (c)δandβcan be partially approximated using interactions among site environment and traits, with a much larger role for environment than traits. The heterogeneity in leaf temperature metrics and energy balance traits challenges larger‐scale predictive models of plant performance under environmental change. A freePlain Language Summarycan be found within the Supporting Information of this article.
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Experimental validation of effective glass transition temperature‐based model for predicting skin thickness in solid‐state microcellular foams
Abstract The solid‐state foaming process produces microcellular foams with an outer layer of solid skin that encapsulates the cellular core. In this article, we implement a 1D model to predict the thickness of the solid skin based on the effectiveTgof the polymer‐gas system for a given foaming temperature. The model is based on the understanding that bubbles nucleate when the foaming temperature exceeds the effectiveTgduring the foaming process. The model was validated with experimental results on the PC‐CO2system, which showed that skin thickness decreases with increased foaming temperature. We also developed a linear correlation to accurately predict effectiveTgat different CO2concentrations. The article also explores the model sensitivity to the key input parameters related to gas diffusion. HighlightsLinear correlation to accurately predict effectiveTgprofiles in PC‐CO2system.Increasing foaming temperature decreases skin thickness.Model is sensitive to the input parameters related to gas diffusion.
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- Award ID(s):
- 2032539
- PAR ID:
- 10643788
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Polymer Engineering & Science
- Volume:
- 65
- Issue:
- 1
- ISSN:
- 0032-3888
- Format(s):
- Medium: X Size: p. 100-107
- Size(s):
- p. 100-107
- Sponsoring Org:
- National Science Foundation
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