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In their article, the authors presented the notion and essence of strategic alliances. They also discussed in it benefits and threats that may result from undertaking cooperation of such a type between partner enterprises, determinants of success of the alliances concluded and importance of measurement of their effectiveness for the enterprises taking part in strategic alliances.
Many factors influence the persistence of traces of pharmaceuticals in aqueous environments. Most important are the intensity of light and the presence of inorganic ions as well as organic matter. We studied the impact of some environmental factors (humic acids, NO₃⁻ and NO₂⁻ ions, solar light intensity, and ambient pH) on the stability and kinetics of photo-reactions of paracetamol, naproxen, and diclofenac. It was stated that paracetamol was photoresistant, while naproxen and diclofenac were photoliable. An addition of NO₃⁻ and NO₂⁻ ions or humic acid strongly inhibited photodecomposition of paracetamol. Their presence in the solution of naproxen slowed down its decomposition, while in the case of diclofenac their influence on the kinetics of the photoreaction was neglected. The effect of the presence of the natural matrix on the photoreaction of the studied pharmaceuticals was checked. The influence of certified reference material – a water sample from the Grand River (Canada) and a sample of treated municipal waste – was examined. We observed that the matrix created by treated municipal waste acted as a photo-sensitizer. Its presence in solution accelerated the photodecomposition of all studied compounds.
The behavior of terazosine hydrochloride (TR), representative of the selective at-adrenergic blockers in river water under the influence of sunlight, was tested. Details of the photodegradation process were obtained using principal component analysis (PCA) and multivariate curve resolution alternating least squares (MCRALS) chemometric methods and confirmed by HPLC analysis. Additionally, the impact of some factors important for efficient waste treatment were studied. For this purpose a stability of terazosine aqueous solutions under the influence of UV, UV+H₂O₂, Fenton, and photo-Fenton processes and sunlight was studied. The presence of H₂O₂ and Fe (II) ions increases the rate of transformation. The process of direct photolysis and H₂O₂-assisted photoreaction showed first order kinetics, while dark and photo-Fenton reactions exhibited second-order kinetics.
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