Physical Sciences and Mathematics Commons^™

Algal Biofuel, Feb 5, 2010, Harry Reid Center, University Of Nevada, Las Vegas

Biofuels

News in Brief

1. UVa engineers find significant environmental impacts with algae-based biofuel (Jan-21, 2010)

2. IPCC scientist: Global cooling headed our way for the next 30 years? (Jan 11, 2010)

3. Shining a Light on Plants' Quantum Secret to Boost Photosynthesis (Feb 3, 2010)

Modeling Whole-Tree Carbon Assimilation Rate Using Observed Transpiration Rates And Needle Sugar Carbon Isotope Ratios, Jia Hu, David J. P. Moore, Diego Andrés Riveros-Iregui, Sean P. Burns, Russell K. Monson

School of Natural Resources: Faculty Publications

• Understanding controls over plant–atmosphere CO₂ exchange is important for quantifying carbon budgets across a range of spatial and temporal scales. In this study, we used a simple approach to estimate whole-tree CO₂ assimilation rate (A_Tree) in a subalpine forest ecosystem.
• We analysed the carbon isotope ratio (δ¹³C) of extracted needle sugars and combined it with the daytime leaf-to-air vapor pressure deficit to estimate tree water-use efficiency (WUE). The estimated WUE was then combined with observations of tree transpiration rate (E) using sap flow techniques to estimate A_Tree. …

Catalytic Solar Water Splitting Inspired By Photosynthesis. Homogeneous Catalysts With A Mechanical ("Machine-Like") Action, Gerhard F. Swiegers, G Charles Dismukes, Leone Spiccia, Robin Brimblecombe, Annette Koo, Jun Chen, Gordon G. Wallace

Faculty of Science - Papers (Archive)

Chemical reactions may be controlled by either: the minimum threshold energy that must be overcome during collisions between reactant molecules / atoms (the Activation Energy, Ea), or: the rate at which reactant collisions occur (the Collision Frequency, A) (for reactions with low Ea). Reactions of type (2) are governed by the physical, mechanical interaction of the reactants. Such mechanical processes are unusual, but not unknown in molecular catalysts. We examine the catalytic action and macroscopic properties of several abiological mechanical catalysts and show that they display distinct similarities to enzymes in general. An abiological model of the Photosystem II Water …

Modeling The Vertical Distributions Of Downwelling Plane Irradiance And Diffuse Attenuation Coefficient In Optically Deep Waters, X. J. Pan, Richard C. Zimmerman

OES Faculty Publications

The diffuse attenuation coefficient Kᵈ is critical to understand the vertical distribution of underwater downwelling irradiance (Eᵈ). Theoretically Eᵈ is composed of the direct solar beam and the diffuse sky irradiance. Applying the statistical results from Hydrolight radiative transfer simulations, Kᵈ is expressed into a mathematical equation (named as PZ06) integrated from the contribution of direct solar beam and diffuse sky irradiance with the knowledge of sky and water conditions. The percent root mean square errors (RMSE) for the vertical distribution of Eᵈ(z) under various sky and water conditions between PZ06 and Hydrolight results are typically less than 4%. Field …