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Magnetic response of bovine spleen

Abstract

Bovine spleen has been used as a sample for deep magnetochemical investigation. Temperature dependence of the magnetic susceptibility and field dependence of the magnetization reveal a paramagnetic behaviour that violates the Curie law. The zero-field cooled magnetization and field cooled magnetization experiments show the bifurcation point at ca T C = 20 K and the blocking temperature T B = 10 K confirming a dominating portion of ferritin along with the organic tissue. There is a remnant magnetization at temperature below 20 K and the search for the magnetic hysteresis was positive.

Open access
The Main Characteristics of the Urban Climate in Relation to the Built Space Evolution in Bucharest, Romania

Abstract

The urban climate is a specific type of topoclimate characteristic to big cities, like Bucharest, which is formed due to the horizontal and vertical expansion of the space, the nature of the materials used for constructions, the pollution, and other side effects of the socio-economic activities. The main objective of this study is the analysis of the variability of four main meteorological elements (air temperature, atmospheric precipitation, relative air humidity, duration of sunshine) in Bucharest and its neighboring area, in relation to the built space evolution. In the last decades, Bucharest has been experiencing an exceptional development, materialized both by territorial expansion, as well as structural-functional and architectural-urbanistic transformations. The fact that the population of the city is increasing, correlated with the expansion of the built space area, suggests the intensity of the urban sprawl phenomena. This has numerous side effects, among which is the creation of a specific topoclimate, different from the one in the periphery. As an example, the results of the meteorological analysis showed that the air temperature is higher inside the city, at the Filaret station, with 0.1ºC, than at the periphery (Baneasa station) and the periurban area (Afumati station).

Open access
New Approaches in Biological Wastewater Treatment Aimed at Removal of Organic Matter and Nutrients

Abstract

The article presents the developed anaerobic-aerobic wastewater treatment technologies. These technologies aimed at removing the organic matter, nitrogen and phosphorus by means of microorganisms immobilized on fibrous carrier surfaces. The results of the laboratory research show the high efficiency of milk wastewater treatment. The following degrees of reduction were achieved for the pollutant indicators: COD -86.7-93 %, total nitrogen - 96.9-97.9 %. Compared to the traditional treatment technologies applied in Ukraine, these values are high. The concentration of organic matters and biomass of not attached bacteria decreased in bioreactor chambers. When the purification process ends, a small amount of excess biomass remains; therefore, its self-oxidation and self-regulation occurs as a result of consumption by the organisms occupying higher levels of trophic chains. The use of anaerobic-aerobic bioreactors system for the treatment of wastewater enables achieving high outflow quality and prevents the suspended substances from slipping. Immobilization of microorganisms on the first stage of the technology prevents the formation of big amount of excessive sludge and removes biomass from the bioreactor, which allows the technology even for the heavily polluted wastewater. In reactors containing immobilized microorganisms, the organic matter compounds used in subsequent reactors for phosphate accumulation are split. The presented biotechnology saves electric energy, provides sufficient quality of treatment, and ensure the compliance of treated wastewater with the effluent standards.

Open access
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