Od svih zemljospojeva koji se mogu pojaviti u mrežama srednjeg napona sa stanovišta sigurnosti ljudi i opreme najproblematičniji je zemljospoj u trafostanici srednji napon/niski napon. Naime, ...uzemljivački sustav mreže niskog napona direktno je povezan s uzemljivačem trafostanice. Stoga se svako povećanje potencijala uzemljivača trafostanice direktno prenosi preko nul-vodiča u instalaciju potrošača. Iz navedenih razloga u ovom radu detaljnije se obrađuje problematika određivanja napona nul-vodiča u mreži niskog napona za vrijeme zemljospoja na razini srednjeg napona u pojnoj trafostanici koja je element mreže srednjeg napona s izoliranim zvjezdištem. Prezentiran je računski model za analizu napona nul-vodiča u realnim distribucijskim mrežama. Analizirane su dvije karakteristične distribucijske mreže položene na kraškom terenu. Dobiveni rezultati su uspoređeni s rezultatima mjerenja.
During the June 2010 survey of phytoplankton and physicochemical parameters in the Krka River estuary (eastern Adriatic Sea), a cryptophyte bloom was observed. High abundance of cryptophytes (maximum ...7.9 x 10 super(6) cells I super(-1)) and high concentrations of the class-specific biomarker pigment alloxanthine (maximum 2312 ng I super(-1)) were detected in the surface layer and at the halocline in the lower reach of the estuary. Taxonomical analysis revealed that the blooming species was Plagioselmis cf. prolonga. Analysis of the environmental parameters in the estuary suggested that the bloom was supported by the slower river flow as well as the increased orthophosphate and ammonium concentrations. The first record of a cryptophyte bloom in the Krka River estuary may indicate that large-scale changes are taking place in the phytoplankton community. Such changes could have a major impact in the natural ecosystem dynamics and the maricolture production in the area.
An increasing number of cryptic and pseudo-cryptic species have been found within many newly described diatom species. To resolve the phylogenetic relationships of the genus Pseudo-nitzschia, ...molecular markers are being widely used in combination (or separately) with different morphological characters. Sequence analysis of ribosomal DNA markers (18S, ITS and 28S) and morphological analyses of Pseudo-nitzschia mannii strain (CIM_D-4), isolated from the Telašćica Bay (Adriatic Sea), differentiate it from all other currently reported strains of this species.
We present the first insight to the oceanography of the southeastern Adriatic Sea, where coastal water influenced by Albanian rivers comes into contact with the inflowing oligotrophic Eastern ...Adriatic Current (Ionian Surface Water and Levantine Intermediate Water). A distinct plankton distribution was observed on each side of the shelf break hydrographic boundary in May 2009, during gradual warming of the surface waters. The prochlorophytes accumulated along the nutricline above the shelf and continental slope. The phosphorus limited inshore waters were dominated by a small diatom
Chaetoceros circinalis
, dinoflagellates, cryptophytes, autotrophic picoplankton, and heterotrophic nanoplankton. The offshore surface layer was characterized by bigger nanoplankton (coccolithophorids, green flagellates). Low nutrient concentrations influence relatively low productivity not only above the Albanian shelf but also further to the north along the Montenegrine and Croatian coastal Adriatic Sea.
The ecological preferences of different Phytoplankton types drive their temporal and spatial distributions, reflecting their dependence on certain temperature ranges, light levels, nutrient ...availability and other environmental gradients. Hence, some phytoplankton taxa can be used as water mass tracers (biotracers).
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