INDEX uptake from water

Indirect evidence for solvent exchange can also be gained by in-situ ellipsometry. This technique can provide information of film thickness and optical properties as a function of the electrode potential. Figure 2.19 shows that the film swells during oxidation and shrinks during reduction, in agreement with EQCM measurements. A decrease in the refractive index from 1.42 to 1.38 during oxidation also supports the uptake of water, which has a refractive index of 1.33. 

Fig. 8 a Changes in mass open circles), obtained through a Voigt-based analysis of combined / and D measurements at multiple harmonics, and SPR mass open squares), obtained through an analysis of changes in interfacial refractive index. The difference between the QCM mass and the SPR mass corresponds to the amoimt of coupled water sensed by QCM solid line), b Separation of the contribution to the total mass uptake from adsorbed non-ruptured vesicles open circles) and planar bilayer patches open squares) versus time was made possible, as detailed in [35]... 

Dowdy, D.L., McKone, T.E. (1997) Predicting plant uptake of organic chemicals from soil or air using octanol/water and octanol/air partition ratios and a molecular connectivity index. Environ. Toxicol. Chem. 16, 2448-2456. 

Based on the effects of water status, temperature, and photosynthetically active radiation (PAR) on net CO2 uptake measured over 24-h periods in the laboratory, net CO2 uptake and productivity have recently been predicted month-by-month in the field for agaves and cacti using an environmental productivity index (EPI). EPI is the product of a Water Index, a Temperature Index, and a PAR Index, each of which can have a maximum value of unity when field values of that environmental factor do not limit net CO2 uptake. A Nutrient Index, similarly ranging from 0.00 to 1.00, has recently been proposed to handle edaphic limitations on net CO2 uptake. In distinction to other productivity indices that customarily focus on only one environmental factor, EPI thus incorporates simultaneous effects of water, temperature, PAR, and even nutrients. Using EPI, the productivity of agaves, cacti, and potentially other species can be predicted over wide geographical regions and under any environmental conditions. 

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