Qualitative interpretation of physico-chemical and isotopic parameters in the Krka River (Croatia) assessed by multivariate statistical analysis

Multivariate statistical analyses were applied on the measured physico-chemical (Cd, Pb, Cu, Zn, Mg, Ca, O₂, alkalinity, temperature, pH, SAS, DOC and DIC) and isotopic parameters (δ¹³C and δ¹⁸O) to estimate and distinguish anthropogenic from natural influences to the water system of the Krka River. Analyses were conducted on the data collected during six years from twelve sampling sites. On the basis of orientation, positioning and grouping of parameters arranged by biplots, four main hypotheses were defined and finally statistically confirmed. Thereof, two main and distinct processes occurring in the Krka River could be highlighted: (i) upstream pollution, caused by the inflow of untreated waste-waters of city of Knin and (ii) downstream self-purification, caused by the sedimentation and/or co-precipitation of pollutants coupled by the inflow of clean subterranean water (groundwater recharge). Grouping of (i) hydrological and carbon cycle connected parameters, and (ii) anthropogenically influenced correlated parameters were proposed as a result of statistical analysis. Regarding the pH, it is shown that a stream section influenced by the subterranean inflow of Zrmanja River is statistically significantly different for all sampling campaigns during six years, being lower for about 0.5 pH unit.     

A Novel in Situ Oxidization-Sulfidation Growth Route via self-Purification Process to β-In2S3 Dendrites

A novel in situ oxidization-sulfidation growth route via a self-purification process has been developed to synthesize β-In₂S₃ dendrites. To our best knowledge, this is the first example to prepare dendrites of III-VI compounds, which are expected to show particular physical properties. The X-ray analysis (EDXA), X-ray photoelectron spectra (XPS), Raman spectrum and optical properties of β-In₂S₃ dendrites have also been investigated. It is found that the product is pure In₂S₃ and shows the strong quantum confinement of the excitonic transition expected for the In₂S₃ dendrites.