Immobilization of cesium with alkali-activated blast furnace slag.

Alkali-activated binders (AABs), as a promising alternative to Portland cement, are now being used on a commercial scale in various applications around the world, including hazardous and radioactive waste immobilization. In this paper, the leaching resistance, strength, and nanostructural alteration of alkali-activated blast furnace slag (AABFS) doped with 2 % and 5 % cesium were investigated. The addition of cesium caused a significant increase in the compressive strength of AABFS, followed by mild strength reduction after leaching. AABFS can be considered a potentially efficient matrix for cesium immobilization, since the mean leachability index in both cases (2 % and 5 % of Cs added) was above the threshold value of 6. Both doping with Cs and leaching caused the transformation of the AABFS nanostructure. The majority of the aluminum that was released from the C-A-S-H gel due to leaching remained within the AABFS matrix, initiating gel reconstruction: the C-A-S-H gel was converted to C-S-H gel, and an additional N-(C)-A-S-H gel was also formed. Cesium was preferentially associated with the N-(C)-A-S-H gel rather than with the C-A-S-H gel. The results of this research seem to be in good agreement with the Cross-linked Substituted Tobermorite Model (CSTM).

[Interactions of the most frequently used drugs in the treatment of angina pectoris]. / Interakcije lekova koji se najcesce koriste u lecenju angine pektoris.

It seems that knowledge and evaluation of drug-interactions with organic nitrates, beta-blockers and calcium-channel blockers are of great importance in relation to patients with chronic diseases, who usually take more than one drug, which is in conjunction with the effect of their ageing. Organic nitrates are safe and the most important drug-group in angina pectoris therapy. Beta-adrenoreceptor blocking agents and calcium-channel blockers are involved in interactions with many different drugs (twenty interactions), but only three interactions are evaluated as interactions of high clinical significance (adrenaline, cimetidine and anti-thyroid agents with beta-blockers, and anti-arrhythmic agents, beta-blockers and cyclosporin with calcium-channel blockers), while the others are of moderate or minimal significance. The most desired interactions of these drugs can be avoided: adjustment of dosage, avoidance of fixed-combination, use of adequate form of drug, or alternative drug and, if necessary, elimination of one drug from therapy. Knowledge of these drug-interactions is important for physician's routine practice either in primary health-care or in hospital conditions.