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The agricultural sector is an important branch that leads to significant changes in the national and regional economic structure, as well as in trend formation impacting the economic development of the country. The changes related to the sectoral structure of the branch determine the place the country occupies with respect to its economic development. The present study aims to analyze and compare the relative share of some main economic indicators defining the place and the role of the agricultural sector in the economy of the EU and Bulgaria, the relationship of agriculture to the other sectors, and to evaluate the dynamic changes in the sectoral structure over a longer time period. The study shows that Bulgaria still lags behind the other EU member states from the perspective of restructuring economy and allocating resources from the agricultural sector to the other two sectors.

The hydrogen sorption of materials based on 80 wt.% MgH2 with the addition of 15 wt.% Ni or V and 5 wt.% activated carbons synthesized from polyolefin wax, a waste product from polyethylene production (POW), walnut shells (CAN), and peach stones (CPS) prepared by milling under an inert Ar atmosphere for a period of 1 h, is investigated. All precursors are submitted to pyrolysis followed by steam activation in order to obtain the activated carbons. The hydrogen sorption evaluations are carried out for absorption at 473 and 573 K with pressure of 1 MPa and for desorption at 623 and 573 K with pressure of 0.15 MPa. The composition of the samples after milling and hydrogenation is monitored by X-ray diffraction analyses. The 80 wt.% MgH2–15 wt. %Ni–5 wt.% POW or CAN after absorption–desorption cycling and in a hydrogenated state at 573 K and 1 MPa are analyzed by TEM. [ABSTRACT FROM AUTHOR]

The aim of the present study was to follow out the alterations in some haematological and blood biochemical parameters in cattle spontaneously infected with enzootic bovine leukosis virus with regard to the invivodifferentiation of bovine leukosis stages. The experiment included 76 cows at various ages and body weight. Serological leukosis tests were done by agar-gel immunodiffusion test with a commercial kit of Synbiotiсs (France), containing standardised gp 51 antigen and positive serum approved by the EU. On the basis of haematological results, the cows were divided into three groups: first group – EBL-seropositive with normal haemogramme; second group – EBL seropositive with altered haemogramme and third group – controls. In cows from the first and the second group, a statistically significantly increased blood cell counts was established compared to healthy controls. The total WBC were increased in the second group (leukocytosis) up to 33.21×109/l vs reference range of 5-10×109/l as well as lymphocyte percentages (lymphocytosis) – 81.89% (reference 40–63%). A reduction in the proportion of neutrophils to 12.78% (relative neutropenia) vs the reference range of 22-49% and monocytes (monocytopenia) to 1.78% (reference range 2–6%) was observed. A statistically significant reduction in Ca concentrations (4.41 mg/dl) and higher inorganic phosphate levels (5.28 mg/dl) were established in cows from the second group. Also, ASAT activity was considerably lower – 47.03 U/l, while alkaline phosphatase increased slightly within the reference range up to 167.68 U/l and 165.81 U/l in groups one and two, respectively. The present haematological and whole blood/serum biochemical results in cows spontaneously infected with EBL virus could be used as prognostic markers of the course of the disease, to distinguish the stages of infection with regard to alive diagnostics.

The organic matter of oil shale samples from four major Bulgarian deposits was investigated using thermal and oxidative treatments. Neutral oils from oil shales were obtained by low-temperature pyrolysis. Gas chromatography-mass spectrometry (GC-MS) was used to study the oxidation products and their chemical composition. A stepwise alkaline permanganate degradation of oil shale concentrate at ambient temperature was carried out, affording a high total yield (90 %) of oxidation products and a minimum yield of gas products. Two different types of high molecular substances were detected in oil shales. The results allowed conclusions to be made about the utilization of prospective Bulgarian oil shale deposits as energy sources. [ABSTRACT FROM AUTHOR]

Adsorption of mercury ions on activated carbon, prepared from polymer waste product, polyolefin wax (POW), was studied. The structure and surface properties of the sample are characterized by different methods—N2adsorption, IR spectroscopy, determination of surface oxygen groups. Adsorption studies of mercury(II) from aqueous solution on synthesized activated carbon are investigated under various conditions—agitation time, metal ion concentration, adsorbent quantity, pH. It was established that the adsorption follows both Langmuir and Freundlich isotherms. The activated carbon obtained from POW demonstrates high adsorption capacity toward mercury ions (196.1 mg/g). The results show that Hg2+removal from water solutions increases with the increase of pH from 2 to 5, and slightly decreases at pH > 6. [ABSTRACT FROM PUBLISHER]