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A parameter based on the sum of the concentrations of PO4 and O2 (divided by the Redfield coefficient‐ΔO2/δPO4) is used to separate the contributions of the northern and southern components to deep waters in the Atlantic. This separation allows the amount of radiocarbon lost by radiodecay and the amount of oxygen lost to respiration during residence in the deep Atlantic to be calculated. Maps of these quantities reveal strong west to east gradients and weak north to south gradients consistent with ventilation along the western boundary from both ends of the ocean coupled with mixing outward from the boundary. The O2 and 14C deficiences are highly correlated, suggesting an O2 utilization rate of 12 μm/kg per century. The apparent mean isolation time of water in the deep Atlantic is about 200 years.

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Low temperature two-photon fluorescence excitation microscopy was used to obtain fluorescence spectra of single CdSe colloidal nanocrystals or quantum dots. The fluorescence spectra reveal large, 0.02 eV shifts of the peak emission wavelength on times of the order of 100 s were also observed in some instances. We attribute this behavior to excited state coupling to photoinduced changes at the nanocrystal surface.