3 research outputs found
Classification of natural disasters between the legislation and application: experience of the Republic of Serbia
The paper discusses the definitions of natural disasters and recommends the implementation of definitions and classifications of natural disasters in accordance with those decreed at the Centre for Research on the Epidemiology of Disasters (CRED) and Munich Re insurance Company (Munich RE) for administrative use in the Republic of Serbia. For the Republic of Serbia, the issue of natural disasters is presented both through government documents (e.g. the Law on Emergencies and the National Strategy of the Protection and Rescue in Emergencies) and the survey of the frequency and typology of disasters. Significant discrepancies exist between older and more contemporary classifications of disasters in Serbia. They are especially emphasized in comparison to the CRED and Munich RE classifications and databases. This causes problems in the monitoring, recording and assessment of the effects of natural disasters. It is proposed that definitions be adapted and implemented into legislative and other documents
Pulverized river shellfish shells as a cheap adsorbent for removing of malathion from water: Examination of the isotherms, kinetics, thermodynamics and optimization of the experimental conditions by the response surface method
Introduction/purpose: In this study, we investigated the possibility of removing the organophosphorus pesticide malathion from water using a new adsorbent based on the biowaste of river shell shards from the Anodonta Sinadonta woodiane family, a material that accumulates in large quantities as waste on the banks of large rivers. Two adsorbents were tested - mechanically comminuted river shells (MRM) and mechanosynthetic hydroxyapatite from comminuted river shells (RMHAp). Methods: The obtained adsorbents were characterized and tested for the removal of the organophosphorus pesticide malathion from water. In order to predict the optimal adsorption conditions using the Response Surface Method (RSM), the authors investigated the influence of variable factors (adsorption conditions), pH values, adsorbent doses, contact times, and temperatures on the adsorbent capacity. Results: The best adsorption of malathion was achieved at mean pH values between 6.0 and 7.0. The adsorption data for malathion at 25, 35, and 45 Ā°C were compared using the Langmuir, Freundlich, DubininRadushkevich (DR), and Temkin isothermal models, as well as pseudofirst order, pseudo-second order and Elovic kinetic models for modeling adsorption kinetics. The maximum Langmuir adsorption capacity for MRM and RMHAp at 25 Ā°C was 46,462 mg g-1 and 78,311 mg g-1 , respectively. Conclusion: The results have showed that malathion adsorption on both adsorbents follows the pseudo-second kinetic model and the Freundlich isothermal model. The thermodynamic parameters indicate the endothermic, feasible, and spontaneous nature of the adsorption process