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A novel β-belite cement was prepared, characterized (by chemical and phase composition, particle size distribution, bulk density, specific surface area) and incorporated into mortars based on a mixed binder β-belite-metakaolinite-hydrated lime with different contents of β-belite cement (0, 20, 40, 60, 80 and 100 wt.%). The metakaoline:hydrated lime weight ratio of 1:1 and binder:sand weight ratio of 1:3 were observed in all mortars. The effect of the β-belite cement fraction on the properties of fresh mortars (water:binder ratio needed to achieve the required mortars consistency and initial setting time), on the phase composition (X-Ray diffraction phase analysis and thermogravimetric analyses) and on the structural properties of mortars (compressive strength, flexural strength, bulk density, water absorption, water absorption coefficient, shrinkage) over 1 year of curing was investigated. Freeze and thaw resistance of the mortars after 1 year of curing was also evaluated. Partial replacement of metakaolinite-hydrated lime binder with β-belite cement affected all investigated mortar properties. Significant improvements in mechanical properties and resistance to freezing and thawing cycles were the main advantages.

The leaching behaviour of three metakaolinite-rich materials prepared from granulated kaolin and two kaolinitic claystones in alkaline solutions at room temperature was investigated with the aid of centrifugal separation of clear supernatant from the reaction mixture. Two types of alkaline solutions (sodium or potassium hydroxide and sodium or potassium silicate solution) with two solid/ liquid weight ratios (0.04 and 0.65) were tested in a large time interval (5 min to 336 h). The metakaolinite-rich materials were characterized by XRD, XRF, BET and MIP. Al and Si concentrations in supernatant were analysed using an inductively coupled plasma optical emission spectrometer (ICP-OES), the solid phases were identified by X-ray diffraction. All three metakaolinite-rich input materials are leachable in the applied alkaline solutions, almost independent of the character of the calcined kaolinitic materials, including both less expensive claystones. The concentrations of dissolved Al and Si were mostly higher in an alkaline solution with sodium than with potassium cations. Alkali silicate solutions showed a significantly higher extent of leaching in comparison with alkaline hydroxide solutions. The solids remaining after the leaching in hydroxide solutions showed a presence of zeolites and carbonates, which, was not the case with alkaline silicate solutions.

The degradation of DNA, resulting in information of oligonucleosomal fragments, is a characteristic feature of apoptosis, i.e., the process of programmed cell death. In this work we have developed a method for exact determination of the proportion of fragmented DNA in an apoptotic cell population. To this end we employed Sephacryl gel chromatography matrices and UV detection of DNA concentration. The disturbing effect of low-molecular-mass UV-absorbing contaminants was eliminated by insertion of a Sephacryl S-200 HR pre-column. Optimum resolution of DNA samples isolated from apoptotic cells was achieved using a triad of Sephacryl S-200 HR, Sephacryl S-500 HR and Sephacryl S-1000 SF columns.