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Kirova-Yordanova Z.,University Professor Dr. Assen Zlatarov Burgas
Energy | Year: 2010

The exergy method is used to compare different production processes and various methods for emission abatement with respect to their overall environmental impact. Some ammonium nitrate production processes are studied as examples, because the pollutants (ammonia and ammonium nitrate), emitted from these processes into the air and/or into the water, are really a feedstock and a product from the production process. Therefore, the essential result of the waste flows treatment is the recycling of the pollutants (ammonia and ammonium nitrate) back into the production process, decreasing simultaneously the exergy input and cumulative exergy consumption. © 2010 Elsevier Ltd.

Kirova-Yordanova Z.,University Professor Dr. Assen Zlatarov Burgas
Energy | Year: 2011

In this work the exergy method is used to compare various methods for removal of NO. x from waste (tail) gas released into the atmosphere from nitric acid production plants with respect to their overall environmental impact. Three basic methods for NO. x abatement are analysed: selective catalytic reduction (SCR), non-selective catalytic reduction (NSCR) and extended absorption. The positive and negative effects and the net effect from the NO. x abatement are calculated. The following exergy-based indicators are used for comparing the energy efficiency and the environmental impact of different treatment processes as a result from pollutants removal: reduction of the exergy of the emissions from the whole process route (ammonia and nitric acid production units); exergy of the additional emissions, arising as a result of the treatment process; total net reduction of the exergy consumption, Cumulative Energy Consumption (CEnC) and Cumulative Exergy Consumption (CExC) of natural resources as a result of the waste flows treatment. © 2010 Elsevier Ltd.

Koleva Y.K.,University Professor Dr. Assen Zlatarov Burgas
Oxidation Communications | Year: 2012

QSAR models based on a narcosis mechanism represent baseline (minimum) toxicity which can be applied for defining excess toxicity of reactive chemicals and their interpreted in terms of the Michael addition mechanistic domain. The aim of the researching was to make an attempt to form mechanistic category for mammalian acute toxicity with regard to their excess toxicity based on baseline acute toxicity model for rat with route of administration oral and an attempt to be applied quantitative and mechanistic read-across using an electrophilicity index (ω) for the Michael acceptors. This study demonstrates the ability of the electrophilicity index (ω) to be used as a measure of similarity for reactive chemicals acting through the Michael addition mechanism. Predictions were made for 15 chemicals for rat within the Michael acceptor domain, with the majority being in good agreement with the experimentally determined values. The mechanism-based read-across is a powerful, transparent, mechanistically interpretable methodology suitable to make computational predictions as part of an intelligent testing strategy.

Risselada A.J.,University Professor Dr. Assen Zlatarov Burgas
Nederlands tijdschrift voor geneeskunde | Year: 2013

The introduction of the new oral anticoagulant drugs (NOACs) has recently been paid much attention. The main advantage of these drugs is that routine monitoring of the anticoagulant effects does not seem necessary. A 53-year-old man who had just undergone partial knee arthroplasty went to the emergency department with shortness of breath and respiratory chest pain. The symptoms arose the day after thromboprophylaxis was switched from dalteparin 5000 IU QD to rivaroxaban 10 mg QD. The patient also used carbamazepine 600 mg BID for epilepsy. Based on a CT scan the patient was diagnosed with pulmonary embolisms. Use of carbamazepine, a CYP3A4 inducer, probably led to an increased clearance of rivaroxaban resulting in pulmonary embolisms. We encourage monitoring of the anticoagulant effects of NOACs in case of drug-drug interactions, especially when NOACs are given in higher doses for a long period, in order to prevent treatment complications.

Krastanov A.,University of Food Technologies | Alexieva Z.,Bulgarian Academy of Science | Yemendzhiev H.,University Professor Dr. Assen Zlatarov Burgas
Engineering in Life Sciences | Year: 2013

Phenol and its derivatives are one of the largest groups of environmental pollutants due to their presence in many industrial effluents and broad application as antibacterial and antifungal agents. A number of microbial species possess enzyme systems that are applicable for the decomposition of various aliphatic and aromatic toxic compounds. Intensive efforts to screen species with high-degradation activity are needed to study their capabilities of degrading phenol and phenolic derivatives. Most of the current research has been directed at the isolation and study of microbial species of potential ecological significance. In this review, some of the best achievements in degrading phenolic compounds by bacteria and yeasts are presented, which draws attention to the high efficiency of strains of Pseudomonas, Candida tropicalis, Trichosporon cutaneum, etc. The unique ability of fungi to maintain their degradation potential under conditions unfavorable for other microorganisms is outstanding. Mathematical models of the microbial biodegradation dynamics of single and mixed aromatic compounds, which direct to the benefit of the processes studied in optimization of modern environmental biotechnology are also presented. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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