Устойчивост на селското стопанство в България

This paper gives answer to topical and debated research and practical questions at the current stage of development of Bulgarian agriculture - „what is sustainability of agriculture", „how to assess sustainability of agricultural in the conditions of EU CAP implementation in the country“, and „which are critical factors for improvement of socio-economic and environmental sustainability in the sector“. Evolution of the „concept“ of agrarian sustainability and the major approached for its assessment are discussed More precise definition of sustainability of Bulgarian agriculture is suggested and the requirements for the system of its assessment are characterised. For the first time a new „governance“ pillar of agrarian sustainability is included along with the universally accepted economic, social and environmental pillars (aspects). Practically applicable for the specific conditions of Bulgarian agriculture holistic framework for assessing sustainability level of agrarian systems of different types (sector, sub-sector, region, ecosystem, agricultural farm) is suggested. The later included 25 principles, 66 criteria, and 163 indicators and reference values for assessing integral, governance, economic, social and environmental sustainability as well as approach for their calculation, integration and interpretation. Approbation of the elaborated framework in assessment of agrarian sustainability at various levels (national, sub-sector, region, (agro)ecosystem, and farm) is made on the base of official statistical, etc, information and original farm surveys. Critical factors for improving sustainability of Bulgarian agriculture are identified, and recommendation made for amelioration of research and assessment practices, public policies and farming strategies for sustainable development. Website of the project: https://zem.alle.b

Устойчивост на селското стопанство в България

This paper gives answer to topical and debated research and practical questions at the current stage of development of Bulgarian agriculture - „what is sustainability of agriculture", „how to assess sustainability of agricultural in the conditions of EU CAP implementation in the country“, and „which are critical factors for improvement of socio-economic and environmental sustainability in the sector“. Evolution of the „concept“ of agrarian sustainability and the major approached for its assessment are discussed More precise definition of sustainability of Bulgarian agriculture is suggested and the requirements for the system of its assessment are characterised. For the first time a new „governance“ pillar of agrarian sustainability is included along with the universally accepted economic, social and environmental pillars (aspects). Practically applicable for the specific conditions of Bulgarian agriculture holistic framework for assessing sustainability level of agrarian systems of different types (sector, sub-sector, region, ecosystem, agricultural farm) is suggested. The later included 25 principles, 66 criteria, and 163 indicators and reference values for assessing integral, governance, economic, social and environmental sustainability as well as approach for their calculation, integration and interpretation. Approbation of the elaborated framework in assessment of agrarian sustainability at various levels (national, sub-sector, region, (agro)ecosystem, and farm) is made on the base of official statistical, etc, information and original farm surveys. Critical factors for improving sustainability of Bulgarian agriculture are identified, and recommendation made for amelioration of research and assessment practices, public policies and farming strategies for sustainable development. Website of the project: https://zem.alle.b

Enhanced Removal of Organic Dyes Using Co-Catalytic Ag-Modified ZnO and TiO2 Sol-Gel Photocatalysts

Zinc oxide and titanium dioxide semiconductor photocatalysts have been widely utilized in the last few decades for water treatment because of their high photocatalytic efficiency. Recently, a lot of researchers have focused on the improvement of the photocatalytic properties of catalysts through modifying and co-modifying them with different metals and nonmetals. These co-catalytic ions improve the photocatalytic activity of ZnO and TiO2 by reducing its energy band gap. This might be useful in wastewater treatment for the photocatalytic degradation of organic contaminants. In this study, we prepared semiconductor films that were surface-modified with Ag co-catalyst layers via the photo-fixation of Ag (I) ions with varied concentrations (10−2–10−4 M) in the water phase under UV illumination for the first time. The photocatalytic behavior was evaluated by the degradation of malachite green and methylene blue under UV and visible light irradiation. The ZnO/Ag and TiO2/Ag samples showed a faster degradation of malachite green compared to methylene blue due to the formation of stable intermediates by the reaction of OH radicals with the triarylmethane dye (C=C bond) during the photocatalysis. The co-catalytic-silver-modified films had a higher photocatalytic efficiency in comparison with the pure nanostructures. The dye photodegradation rate constants increased in the following order: pure films < films modified with Ag, 10−4 M < films modified with Ag10−3 M < films modified with Ag10−2 M. The Ag modification and the heterojunction of the composites contributed to trapping and transfer of the electrons. Therefore, the photogenerated charges had a longer lifetime, resulting in a strengthened photocatalytic ability of the ZnO/Ag and TiO2/Ag films

Enhanced Removal of Organic Dyes Using Co-Catalytic Ag-Modified ZnO and TiO₂ Sol-Gel Photocatalysts

Zinc oxide and titanium dioxide semiconductor photocatalysts have been widely utilized in the last few decades for water treatment because of their high photocatalytic efficiency. Recently, a lot of researchers have focused on the improvement of the photocatalytic properties of catalysts through modifying and co-modifying them with different metals and nonmetals. These co-catalytic ions improve the photocatalytic activity of ZnO and TiO2 by reducing its energy band gap. This might be useful in wastewater treatment for the photocatalytic degradation of organic contaminants. In this study, we prepared semiconductor films that were surface-modified with Ag co-catalyst layers via the photo-fixation of Ag (I) ions with varied concentrations (10−2–10−4 M) in the water phase under UV illumination for the first time. The photocatalytic behavior was evaluated by the degradation of malachite green and methylene blue under UV and visible light irradiation. The ZnO/Ag and TiO2/Ag samples showed a faster degradation of malachite green compared to methylene blue due to the formation of stable intermediates by the reaction of OH radicals with the triarylmethane dye (C=C bond) during the photocatalysis. The co-catalytic-silver-modified films had a higher photocatalytic efficiency in comparison with the pure nanostructures. The dye photodegradation rate constants increased in the following order: pure films −4 M −3 M −2 M. The Ag modification and the heterojunction of the composites contributed to trapping and transfer of the electrons. Therefore, the photogenerated charges had a longer lifetime, resulting in a strengthened photocatalytic ability of the ZnO/Ag and TiO2/Ag films

Influence of Non-Ionic Surfactant and Silver on the Photocatalytic Activity of TiO₂ Films for Degradation of Dyes in Distilled and Tap Water

This study describes the impact of surfactant molecular weights (PEG 2000 and PEG 4000) on the photocatalytic activity of TiO2 films, deposited via dip-coating from a PEG-stabilized suspension and silver-functionalized photo-fixation of Ag+ under UV illumination. The photocatalytic activity of pure and Ag/TiO2 films is assessed in the aqueous-phase degradation of Malachite green and Methylene blue in distilled and tap water under UV and visible illumination. The results indicate a positive effect of both the higher-molecular-weight non-ionic surfactant and Ag-functionalization yield higher photocatalytic efficiency. Notably, films photo-fixed with 10−2 M Ag+ show the highest degradation percentages in all experimental conditions. A direct correlation between the concentration of Ag+ ions and the enhancement of the photocatalytic activity is revealed: pure TiO2 −4/TiO2 −3/TiO2 −2/TiO2. Flame atomic absorption spectrometry is used to study the Ag+ leeching from the Ag/TiO2 films. The structural properties of the nanostructures are investigated through scanning electron microscopy, Brunauer–Emmett–Teller analysis, energy-dispersive X-ray spectroscopy, and X-ray diffraction. Additionally, after three cycles of operation, Ag, 10−2/TiO2 (PEG 4000) films can maintain their photocatalytic activity, suggesting a potential application in the treatment of dye wastewater

Human Parasitic Diseases in Bulgaria in Between 2013-2014

Parasitic diseases are a significant part of the overall pathology registered in Bulgaria. It is essential to constantly improve the efficiency of the public health system in order to deal with autochthonous parasitic disease

Студентска научна конференция "Здравеопазването-днес и утре", 22 Май 2013, Варна

Варненски медицински форум (Varna Medical Forum) V. 2, Suppl 4 (2013