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Numerical Prognosis of Dispersion and Transport of Pollutants in Romania, Based on Emissions of Pollutants

Abstract

Air pollution is one of the major problems of mankind, transport of pollutants extending far beyond the borders of the countries where they were produced, causing unpredictable, direct and indirect changes of the environment. The main tool for the study of this phenomenon consists of mathematical modeling of complex physical and chemical phenomena involved. In practice, air emissions are estimated on basis of measurements taken from selected sources being representative of the major categories and types. At national level, the Air Quality Evaluation Center (CECA) provides regular reports to the European Environment Agency (EEA) or the European Commission as requirements of Romania’s lawful duties in air quality domain. The registry of emissions TNO/ MACC (Netherlands Organisation for Applied Scientific Research/ Monitoring Atmospheric Composition and Climate) contains emissions inventories which have been homogenized and checked in advance and obtained from emissions officially reported at sectoral level for each country. In this study, for the analysis of the weather numerical dispersion and transport of pollutants, it has been used the numerical air quality model WRF-CHEM version 3.5, centered over Romania, at the spatial resolution of 10 km, using as input data the TNO emission database for 2009. By interpolating values from the regular grid of the TNO database with the WRF-CHEM model 3.5 grid, monthly average values were obtained for each day of the week, for any parameter considered. Preliminary results obtained for different pollutants (for example: PM10, O3) confirm the need to validate these results by implementing and integrating air quality forecasting model by assimilating different types of measurements (data model, gravimetric data observations, etc.).

Open access
Onsome New Neighbourhood Degree Based Indices

Abstract

In this paper, four novel topological indices named as neighbourhood version of forgotten topological index (FN), modified neighbourhood version of Forgotten topological index (FN*), neighbourhood version of second Zagreb index (M2*) and neighbourhood version of hyper Zagreb index (HMN) are introduced. Here the relatively study depends on the structure-property regression analysis is made to test and compute the chemical applicability of these indices for the prediction of physicochemical properties of octane isomers. Also it is shown that these newly presented indices have well degeneracy property in comparison with other degree based topological indices. Some mathematical properties of these indices are also discussed here.

Open access
Payments for Forest Ecosystem Services Across Europe – Main Approaches and Examples from Slovakia

Abstract

Payments for ecosystem services (PES) are flexible, financial mechanisms for utilisation of available finances for environmental improvement. Payments for forest ecosystem services (PFES) have gained increasing policy acceptance at national and international levels. However, evidence about their implementation is limited and rather mixed. PES design is a complex task. There are a number of PES design features that need careful understanding of the specific ecological and socio-economic context. The aim of this article is to analyse main approaches to PFES and types of PES schemes or financial arrangements with the emphasis on three basic schemes: (i) public schemes or government-financed PES (Pigouvian type), (ii) private schemes or user-financed PES (Coasean type) and (iii) public–private schemes (a mixed type). The empirical part is based on the review of PES schemes implemented in different Forest Europe signatory countries. The main features of PES schemes are described on chosen examples from Slovakia.

Open access
Perspectives of Hydrogen Production from Corn Wastes in Poland by Means of Dark Fermentation

Abstract

A model for calculating the maximal theoretical production of hydrogen from corn wastes is proposed. The model has been used to estimate the potential for hydrogen production from cereals wastes such as wheat, barley, and corn which are cultivated in Poland. The potentials for Pomorze and other regions of Poland are compared. The hydrogen produced from cereal wastes in Poland could potentially meet 47 % of national hydrogen demand.

Open access
Phytotoxicity of colloidal solutions of stabilized and non-stabilized nanoparticles of essential metals and their oxides

Abstract

Advances in nanotechnology in various fields of human activity contribute to increase of their production, improved properties and wider implementation of nanomaterials. However, increasing use may enhance their release into the environment and can lead to affecting human health. The toxicity of colloidal solutions of metal nanoparticles (Cu, Mn) and their oxides, obtained in the absence and presence of a stabilizer, was examined and compared with the use of the standard test system of Allium cepa L.. The phytotoxicity of the experimental solutions was evaluated according to the growth response of the onion roots; the cyto- and genotoxicity were estimated due to the proliferative activity of the root meristem cells. It was established that solutions of stabilized metal nanoparticles were at given concentration toxic to Allium cepa L. according to the integral index of roots growth, however, were not cytotoxic. Difference in the phytotoxicity of stabilized and non-stabilized metal nanoparticles and their oxides depended on their phase composition and affected root growth.

Open access
The Possibility of Contamination of Water-Soil Environment as a Result of the Use of Pig Slurry

Abstract

Pig slurry is a heterogeneous mixture of faeces, urine, undigested remains of feed items and water used for flushing of animal excrement and to maintain the proper hygiene of livestock housing. It is formed on farms which use the non-bedding system of pig breeding i.e. animals are kept on the partially or fully slatted floors. According to the Polish law pig slurry is defined as a liquid natural fertilizer intended for agricultural use. The storage and application of pig slurry on arable land affect the surroundings and may create a number of serious risks related to, among others, the pollution of water-soil environment with biogenic elements, heavy metals, pathogens and pharmaceuticals. The article presents the reasons for the occurrence of excessive amounts of nitrogen, phosphorus, copper, zinc and antibiotics in pig slurry. The possibility of microbial and pharmaceutical contamination of water, soil and plants as well as their pollution with biogens and heavy metals as a result of improper storage and excessive spreading of pig slurry have been characterized. Moreover, methods of preventing the above-mentioned threats with reference to Polish and EU legal acts have been discussed.

Open access
Preparation and Characterization of Spion-CDs as a Multifunctional Fluorescence/Magnetic Resonance Nanoparticle

Abstract

A multifunctional nanoparticle, Super Paramagnetic Iron Oxide Nanoparticle-Carbon Dots (SPION-CDs), for fluorescence and magnetic resonance imaging is introduced. This nanoparticle possesses the magnetic properties of super-paramagnetic iron oxide (SPION) core as well as the fluorescence characteristics of carbon dots (CDs) coated in mesoporous structure. The SPION-CDs were synthesized using a high temperature facile single-pot hydrothermal method. The products were characterized by transmission electron microscopy (TEM), dynamic light scattering (DLS), X-ray diffraction (XRD), UV/vis absorption, vibrating sample magnetometer (VSM). The cytotoxic effect of SPION-CDs on OVCAR-3 cells was also evaluated. The synthesized nanoparticle possesses optimal size, low toxicity and excellent magnetic properties, including super-paramagnetic behavior (Ms = 42 emu g−1). Moreover, in the viewpoint of optical properties, the quantum yield of ~2.4% was obtained and the nanoparticle shows good fluorescence stability for cell-labeling studies. This multifunctional nanoparticle with appropriate characterization is a promising candidate for multimodal fluorescence/magnetic resonance imaging platform.

Open access
Programs for Prevention and Management of Natural Disasters in the European Countries of The Larger Area of The Black Sea Basin

Abstract

The hazards that have cross-border consequences and represent a great problem for communities, become an obstacle to sustainable development and lead to disasters when combined with vulnerability and insufficient capacity to mitigate the risk. A short overview of research already implemented and in progress presents us a shift in systematic evaluation of the hazards and disasters at local and areal level. Hazard assessment of natural disasters (earthquakes, landslides and floods) on these scales can give results which can be directly used to take right decisions regarding preventive measures and plan effective actions of post-event management. The issue is widely recognized in the european union (eu) implicitly also in the black sea area, and a lot of efforts have already been made to mitigate the effects of disasters, obviously through the formation of numerous eu institution, established organizations and funded projects. The key elements for an effective mitigation of natural disasters are hazard identification and risk assessment, which must be based on scientifically grounded methodologies, reliable and accurate data. Successful resolution of the issues mentioned above will provide the ability to systematically assess natural disasters on regional and local scales, even in cross-border areas, by providing comparable hazard maps that will support the decision-making process in relation to mitigation measures required. The effective way of action against them is by providing applied research and technology transfer between partners in different countries by solving the problems such as lack of reliable information and lack of 'common ground' in the methodologies used to assess natural hazards and adopted procedures for mitigation.

Open access
Projections of Climate Suitability for Wine Production for the Cotnari Wine Region (Romania)

Abstract

Climate projections have revealed the perspective of changing the climate of the world's wine regions in the coming decades by diversifying heliothermal resources. Research in the Cotnari winegrowing region over the past decade has shown that the local climate has been affected by such developments especially after 1980. This research continues the series of studies on the climate of the Cotnari winegrowing region through projections of the climatic conditions for the 2020-2100 time period based on the RCP 4.5 scenario. Average annual temperature, warmest month temperature, precipitation during the growing season, length of the growing season and the Huglin, IAOe and AvGST bioclimatic indices for the 2020-2050, 2051-2080 and 2081-2100 time periods indicate the evolution of Cotnari area climate towards suitability for red wines and loss of suitability for the white wines. Climatic suitability classes for wine production, shift between 2020-2100 to the higher, cooler zone of the winegrowing region, narrowing down their surface and disappearing successively at the maximum altitude of 315 m asl. They are further replaced from the lower zone by classes specific to warmer climates. The suitability for white wines, specific to wine region, disappears at the maximum altitude of 315 m asl around 2060, being replaced by climate suitability for the red wine production. The average temperature of the growing season will exceed 19.5°C after 2080, becoming unsuitable for the production of red quality wines of Cabernet Sauvingnon variety. After 2050, in the lower zone of the winegrowing region the warm IH5 class, suitable for Mediterranean varieties such as Carignan and Grenache will install, as compared to temperate IH3 class which characterizes today the lower zone and allows the production of white wines of the local Feteasca albă, Grasa de Cotnari, Frâncușa and Tămâioasa românească varieties. The results suggest the need to develop strategies for adapting the viticulture of the Cotnari area to climate change.

Open access
Radiation induced degradation of Congo red dye: a mechanistic study

Abstract

Synthetic dyes are persistent pollutants with poor biodegradability. The present study is about the degradation of direct Congo red dye in aqueous media using the Co-60 gamma radiation source. The experimental conditions such as gamma-ray absorbed doses, amount of oxidant (H2O2) and pH conditions were evaluated. The λmax of dye solution was noted as 498 nm, and then, decrease in absorbance and reduction in chemical oxygen demand (COD) were examined. The complete colour removal of dye was observed at 5 kGy, while a significant COD removal was observed at 15 kGy gamma-ray absorbed dose in conjunction with oxidant for 50 mg/L concentration. It was found that pH has no influence on degradation efficiency. A possible degradation pathway was proposed. The radiolytic end products were monitored by Fourier transform infrared (FTIR) and gas chromatography coupled with mass spectrometry (GC-MS) to explore the degradation mechanism. It was imperative to study the oxidative degradation pathway to provide directions for potential applicability of advanced oxidation process (AOP) in industrial wastewater treatment.

Open access