Edible snails are kept in farms in many countries worldwide. As farm animals, they are an object of interest of veterinary studies and applied biology. There is a large demand for tests which would help identify their health and well-being. The objective of this study was to assess the usefulness of determining the concentration of urea in hemolymph as a marker of health of the Lissachatina fulica and Cornu aspersum edible snails. The observation covered snails from four farms marked from A to D, in which numerous deaths (farm A) and decreased body weight gain (farms B and C) were observed. In experimental farm D we observed a group of snails subjected to stress and a control group maintained in correct conditions. High concentrations of urea were found in the hemolymph of all farm animals from farms A, B and C, as well as in those subjected to food deprivation in farm D (on average from 96 mg/dl in farm D to 320 mg/dl in farm A). On the other hand, in controls from group D, the concentration of the parameter in question was much lower (< 2.0 mg/dl). The results obtained indicate that the urea concentration is a non-specific marker of pathological conditions in snails, and that the continuous monitoring of this parameter makes it possible to demonstrate irregularities in farming and introduce appro- priate and early measures to eliminate such disturbances.

Catalytic properties of activated carbons oxidized, treated with N-compounds, and promoted with copper were studied in selective catalytic reduction NOX by ammonia (NH3-SCR). The modification of the catalysts consisted of a series of steps (pre-oxidation of activated carbon, impregnation with urea, impregnation with copper). The physicochemical properties of the obtained samples were determined using X-ray diffraction, FT-IR spectroscopy, and low-temperature N2 sorption. The modification with copper improved the catalytic activity and stability of the catalysts. All the functionalized carbon doped with copper reached more than 90% of NO conversion and CO2 did not exceed 240 ppm at 220 ◦C. The sample doped with 5 wt.% Cu had the maximum NO conversion of 98% at 300 ◦C. The maximum N2O concentration detected for the same sample was only 55 ppm, which confirmed its selectivity.

Following compounds were determined in samples from Bransfield Strait and southern part of Drake Passage (area "A"): dissolved free- and combined amino acids, dissolved mono- and polisaccharides and urea. Concentration of urea in most samples ranges from traces to 1.5 μgat Nurea-1 and total urea content in water column from 10 to 150 m lies between 19.23 and 197.4 mgat Nurea . Dissolved free amino acids concentration ranges from 0 to 0.60μg x 1-1 and total free amino acid content are found to be between 20 and 60 mmol. Concentrations of combined amino acids lay below 7 μmol x 1-11 and integrated value for combined amino acids fluctuates between traces and 450 mmol. Monosaccharides concentrations in most samples do not exceed 2.5 μmol x l-1 and their content in water column lies below 180 mmol. Polysaccharides content in water column ranges from 1.8 to 3.94 mol and concentrations vary between 8 and 32 //mol-1 1. Evident differences in the content of dissolved organic compounds between Bransfield Strait and southern part of Drake Passage were found.