Spectral solar photon irradiance in Central Europe and the adjacent North Sea

APEX (Aqueous Photochemistry of Environmentally occurring Xenobiotics): a free software tool to predict the kinetics of photochemical processes in surface waters

“…The model has been 55 validated by comparison with field data, showing good agreement. APEX is based on the free software Octave.…”

“…We have recently developed a photochemical model that predicts photochemical reactions and pollutant phototransformation as a function of water chemistry and of the 55 optical path length of sunlight in water, the latter being proportional to water depth. The model relies as key input data on pollutant photoreactivity parameters such as the direct photolysis quantum yield and the second-order reaction rate constants with • OH, CO 3 −• , 1 O 2 and 3 CDOM*.…”

“…This will improve the accuracy of model predictions for photochemical processes taking place in that environment. 55 The apex.m function makes calculations on the basis of input data and instructions, using the model equations that are listed in detail in the User's Guide (see ESI). Many of the relevant equations require integration over wavelength, which is carried out numerically by the integral.m function.…”

A model approach to assess the long-term trends of indirect photochemistry in lake water. The case of Lake Maggiore (NW Italy)

“…We assume d as the water column depth in cm (in this study, d = 500 cm), A tot (λ) = A 1 (λ) d as the total absorbance of the water column, and p°(λ) as the incident spectral photon flux density of sunlight. The sunlight p°(λ) shows a seasonal variation (see Figure 1 in the Supplementary Material, hereafter SM) (Frank and Klöpffer, 1988). CDOM is by far the main radiation absorber between 280 and 450 nm (Bracchini et al, 2010),…”

Photochemischer und photokatalytischer Abbau von Carbamazepin, Clofibrinsäure, Iomeprol und Iopromid

“…Die spektrale Photonenstromdichte steigt mit zunehmender Wellenlänge bis zu ca. 550 nm zunächst an und behält dann einen konstanten Wert [36,37]. Für die solare Photochemie am Boden ist der Wellenlängenbereich der Strahlung von 300 bis 500 nm von großer Bedeutung, da die Photonen mit 399 bis 240 kJ/Einstein ähnliche Energiebeträge wie chemische Bindungen (C-H: 415 kJ/mol und C-C: 350 kJ/mol) aufweisen.…”