30 research outputs found

    Soil pollution in the Hungarian-Romanian border region (Valley of Körös-Cris rivers)

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    The investigation assessed and evaluated the soil polluting activities in 30 Romanian and Hungarian settlements in the region of the Double, Black and White Körös-Cris Rivers. Pb concentrations are mainly higher than the limit values with maximum values registered in the area of landfill and near the roads. The concentration of Cu and Zn in soils of the region is below the alarming values. In some places Cd levels in soils reached the alert threshold. Plant samples mostly do not contain higher than permitted levels of heavy metals. One of the main goals of the study is to contribute to the future sustainable use of the environment and conservation actions in the region in order to implement regional development policy. We must therefore address the social activities that involve a risk of soil pollution in the region, especially in the Körös-Cris Valley. Science-based assessment of the level of pollution can lead to the development of implementing procedures to reduce the impact of these activities. The most important result of the quality and quantity analysis of polluting activities in the region is territorial definition of soil heavy metal load

    Soil pollution in the Hungarian-Romanian border region (Valley of Körös-Cris rivers)

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    The investigation assessed and evaluated the soil polluting activities in 30 Romanian and Hungarian settlements in the region of the Double, Black and White Körös-Cris Rivers. Pb concentrations are mainly higher than the limit values with maximum values registered in the area of landfill and near the roads. The concentration of Cu and Zn in soils of the region is below the alarming values. In some places Cd levels in soils reached the alert threshold. Plant samples mostly do not contain higher than permitted levels of heavy metals. One of the main goals of the study is to contribute to the future sustainable use of the environment and conservation actions in the region in order to implement regional development policy. We must therefore address the social activities that involve a risk of soil pollution in the region, especially in the Körös-Cris Valley. Science-based assessment of the level of pollution can lead to the development of implementing procedures to reduce the impact of these activities. The most important result of the quality and quantity analysis of polluting activities in the region is territorial definition of soil heavy metal load

    Neintelektualni prediktori postignuća u matematici

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    Findings presented herein are a part of a large international study of primary school final grade student achievement in mathematics and science (TIMSS 2003). Studies were also conducted on the degree of correlation between student family socioeconomic status, mathematical self-concept and achievement in mathematics. Pilot studies, whose findings are discussed comprised 112 seventh-grade students. "Family socioeconomic status" was defined by variables such as the number of family members, economically disadvantaged/affluent home, and parental educational status. "Mathematical self-concept" was defined as one of the more narrow domains of academic self-concept. "Achievement in mathematics" was measured by the test assessing two dimensions of knowledge of mathematics: content and cognitive skills. The analyses of partial correlations indicate that the most significant predictors of achievement in mathematics test are as follows mathematical self-concept, mother’s educational status and some indicators of family socioeconomic status (access to the Internet, number of household members, number of books available at home). Concerning the correlation found between family characteristics and mathematical self-concept and achievement in mathematics, the developers of current changes in mathematics teaching should not disregard the findings of this study.U radu su izloženi nalazi koji predstavljaju deo obimnog međunarodnog istraživanja obrazovnih postignuća učenika završnih razreda osnovnih škola u oblasti matematike i prirodnih nauka (TIMSS 2003). Ispitivan je, pored ostalog, stepen povezanosti socioekonomskog statusa porodice, matematičkog koncepta o sebi i postignuća u matematici učenika završnih razreda osnovne škole. Probnim istraživanjem, o čijim je nalazima reč, obuhvaćeno je 112 učenika VII razreda jedne gradske i jedne prigradske osnovne škole u Beogradu. Matematički koncept o sebi definisan je kao jedan od važnih domena akademskog koncepta o sebi i ispitivan je posebnim upitnikom za učenike. Analiza parcijalnih korelacija ukazuje da su najznačajniji prediktori postignuća na testu iz matematike: matematički koncept o sebi, obrazovni status majke i neki indikatori socioekonomskog statusa porodice (dostupnost interneta, broj članova domaćinstva, broj knjiga u kući). S obzirom na to da je utvrđena povezanost između karakteristika porodice i matematičkog koncepta o sebi sa postignućem u matematici, kreatori aktuelnih promena u nastavi matematike trebalo bi da imaju u vidu i nalaze ovog istraživanja

    The impact of the July 2007 heat wave on daily mortality in Belgrade, Serbia

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    Objective: Mortality has been shown to increase with heat waves. Serbia experienced the hottest heat wave in July 2007. In this study, we examined patterns of non-traumatic excess mortality in Belgrade during this event. Methods: The numbers of deaths observed during the 9-day heat wave were compared to those expected on the basis of mortality rates reported for the previous eight years and two following years. Excess mortality was analyzed by age, gender and cause of death. Results: There was a total of 167 excess deaths (38%) between 16 and 24 July. People aged 75 years and older accounted for 151(90%) of all excess deaths. An increase of mortality among elderly was 76% in comparison to the baseline mortality. Excess female mortality was over two times higher than excess male mortality (54% : 23%). The biggest increase in mortality was from diabetes mellitus (286%), chronic kidney disease (200%), respiratory system diseases (73%), and nervous system diseases (67%). Cardiovascular and malignant neoplasms mortality accounted for the highest absolute numbers of excess deaths (77 and 49, respectively). There was no decrease in mortality in the 60-day period after the heat wave. Conclusions: There are several causes of an increase in heat-related mortality. The most vulnerable population group is the elderly females

    Outdoor human thermal comfort in local climate zones of Novi Sad (Serbia) during heat wave period

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    Urban climate monitoring system (UCMS) was established in Novi Sad (Serbia) in 2014 based on the Local Climate Zones (LCZs) classification system, GIS model calculations and field work. Seven built and two land cover LCZ types were delineated and 27 stations equipped with air temperature and relative humidity sensors were distributed across all LCZs. Suitability of the developed monitoring system for human outdoor thermal comfort research in different LCZs of the city and its surroundings was investigated during a heat wave period using Physiologically Equivalent Temperature (PET) index. During the daytime (night-time) the highest thermal loads are present in open midrise (compact midrise) LCZ, while the most comfortable is LCZ A (dense trees) during the whole day. In general, the highest thermal loads are obtained in midrise, followed by low-rise, sparsely built, low plants and dense trees LCZs. All LCZs (except LCZ A - dense trees) had higher PET when compared to LCZ D (LCZ D - low plants) during evening and nocturnal hours with maximum difference of 7.1 °C (00 UTC) between LCZ 2 (compact midrise) and LCZ D (low plants). Contrary to this, LCZ D (low plants) had higher PET compared to the majority of LCZs during the daytime with maximum difference of 8.5 °C (9 UTC) when compared to LCZ A (dense trees). Furthermore, the smallest thermal comfort differences during heat wave occurred between LCZs with similar structure (i.e. open low-rise and large low-rise, compact midrise and compact low-rise) and cover (i.e. sparsely built and low plants)

    Purification of waste water using ozonization

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    Usled razvoja industrije i rastom populacije tokom poslednjih godina javljaju se problemi u vezi sa otpadnim vodama iz proizvodnje koje je neophodno rešavati na ekološki i ekonomičan način. Sve otpadne vode iz postrojenja bez obzira kako su nastale sadrže štetne materije koje mogu da imaju i određen stepen toksičnih primesa, moraju se prečistiti ako njihov kvalitet ne odgovara zakonskim okvirima. Svrha tretmana otpadnih voda je uklanjanje štetnih materija čime se postiže smanjnje stepena njene zagađenosti, a istovremeno se ostvaruje i određen ekonomski i ekološki efekat, stoga je u ovom radu izvršeno prečišćavanje otpadne vode postupkom taloženja upotrebom kalcijum-oksida u cilju uklanjanja koloidnih materija i teških metala. Većina zagađujućih materija su organskog porekla i njihovo ukljanjanje vršiće se primenom naprednih oksidacionih procesa korišćenjem ozona i ozona u kombinaciji sa ultrazvukom u cilju postizanja kvaliteta vode koji odgovara zakonskoj regulativi. Proces prečišćavanja će se optimizovati u odnosu na tehnološki postupak, koncentraciju, vreme tretmana i količinu primenjenog oksidacionog sredstva. Stepen zagađenosti vode organskim jedinjenjima će se određivati na osnovu merenja HPK, BPK i koncentracije teških metala (olovo, gvožđe, hrom, bakar, cink, aluminijum).Due to the development of industry and population growth during the in recent years, there are problems with wastewater from production that needs to be addressed in an environmentally and economical way. All wastewaters from industry, no matter how they are created, contain harmful substances that may have some degree of toxicity, must be treated if their quality does not meet the legal requirements. The purpose of wastewater treatment is to remove harmful substances, thereby reducing its pollution level, and at the same time, it also has a certain economic and environmental effect. Therefore, wastewater treatment was carried out in this work by precipitation using calcium oxide to remove colloidal substances and heavy metals. Most pollutants are of organic origin and their removal will be carried in this work out using advanced oxidation processes using ozone, and ozone in combination with ultrasound to achieve water quality that complies with the law. The purification process will be optimized with respect to, method, time and amount of oxidizing agent applied. The degree of pollution of water by organic compounds will be determined on the basis of measurements of HPK, BOD and the concentration of heavy metals (lead, ferrum, chromium, copper, zinc, aluminum)

    Critical exponents at the ferromagnetic transition in tetrakis(diethylamino)ethylene-C60_{60} (TDAE-C60_{60})

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    Critical exponents at the ferromagnetic transition were measured for the first time in an organic ferromagnetic material tetrakis(dimethylamino)ethylene fullerene[60] (TDAE-C60_{60}). From a complete magnetization-temperature-field data set near Tc=16.1±0.05,T_{c}=16.1\pm 0.05, we determine the susceptibility and magnetization critical exponents γ=1.22±0.02\gamma =1.22\pm 0.02 and β=0.75±0.03\beta =0.75 \pm 0.03 respectively, and the field vs. magnetization exponent at TcT_{c} of δ=2.28±0.14\delta =2.28\pm 0.14. Hyperscaling is found to be violated by Ωdd1/4\Omega \equiv d^{\prime}-d \approx -1/4, suggesting that the onset of ferromagnetism can be related to percolation of a particular contact configuration of C60_{60} molecular orientations.Comment: 5 pages, including 3 figures; to appear in Phys. Rev. Let

    Forest fire analysis and classification based on a Serbian case study

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    A recent forest fire in the Republic of Serbia is discussed concerning classification, legislative framework and fire management, giving a detailed analysis of the forest fire occurrence. Analysing past and predicting future fires are crucial for policy development and forest management practices to prevent and mitigate fires. Fire hazard is discussed through several fire protection and prevention legislative documents. The nonparametric Mann-Kendall test was used to analyse resent forest fire data in an attempt to find causality in occurrences and frequency. The meteorological data and fire statistics provided by the Serbian Hydro-meteorological Service and the Ministry of Interior/Sector for Emergency Management of the Republic of Serbia were used to calculate the Forest Fire Weather Indices, along with deficit or surplus of precipitation for the case study of Tara Mountain. The paper highlights the need for better hierarchical classification of fire hazards and its harmonisation along with standardisations presented by leading international research institutions. A significant correlation between meteorological parameters and forest fire occurrence was found. This opens a possibility for further investigation and analysis of geophysical and anthropogenic driven factors that can influence disaster occurrence
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