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The Proces of producting building materials, their transport to the building site, usage in bulding and the usefulness of those buldings are classified as a part of the largest group of energy consumers. According to some new researches, the energy consumption during the object’s exploitation in Serbia are somewhere between 100-250 kWh/m2, but the Standard for new objects that are being constructed in many EU countries is 40KWh/m2, in some even 20 kWh/m2. By the new Law of Construction and Spatial Planning the energy efficiency of buildings is set as the priority in the construction of new buildings. The Rule Book of Energy Efficiency (Official Gazette 61/2011 from 19.08.2011) that is in use since 30.09.2013. obligates designers and contractors to apply the measures so that the existing and new objects could be energy efficient. The existing high-rise buildings, which were built before the regulation for the thermal protection was adopted, can be made more acceptable, more suitable and less demanding from the energy saving point of view, if materials and installations that can be produce by recycling additionally overlay the facade and roof surfaces. In the EU, recycling industry is represented with 58%, and with only 0.3% in Serbia. Results of the research conducted in 2009-2012. pointed out that 30% of designers have no knowledge of recyclable materials which can be applied in construction, and that 82% of designers don’t know if these materials can be used to improve the energy efficiency of buildings.
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According to the analysis results of air quality monitoring in the national network for monitoring air quality, contained in the report on the status of the Republic of Serbia, as well as published papers (Popović, Jović i Marić 2013a; 2013b) particle pollution has a dominant impact on air quality. According to the Regulation on the conditions and requirements for monitoring of air quality (Fig. Gl. RS, 11/10 and 75/10), which is the implementation of EU legislation and practice into domestic legislation and practice, define the criteria for the assessment of air quality. PM10 are defined characteristic values and the allowed number of days exceeding the daily GV. In this paper we analyze the number of exceedances of daily LV compared to the maximum allowed by the EU and applicable local regulations.
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The paper’s objective is to analyze CO2 emission from petrol and diesel passenger cars. Mathematical model for determination of optimal passenger cards life cycle is used in this paper. Special attention is given to analyze the following life cycle sequences: use, maintenance and recycling. Analyzing the Serbian passenger car fleet, the author noticed the possibilities in reduction of CO2 emission. In this paper is also analyzed impact of imports of used passenger cars on CO2 emission.
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This paper presents some of the most important results of a Bor`s citizens survey about the preparation of the revised LEAP in 2013., who indicated that there has been a significant change in attitudes toward major environmental problems and the ways of addressing them. The survey has showed that the ecological awareness of Bor `s citizens is important factor in solving ecological problems and is therefore included within the LEAP. It`s further strengthening is defined as one of the priorities of environmental policy in the future.
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This paper employs a systems GMM model using data on 43 Sub-Saharan African countries from 1960 to 2005 to find that natural disasters have a significant impact on migration from SSA, raising the net out-migration by around 0.37 persons per 1,000. No direct evidence was found that natural disasters lead to further migration through impacting on GDP growth. It is however established that natural disasters is associated with a slightly increased probability that a country will be in conflict in a subsequent period. The frequency of natural disasters will not influence the duration of the conflict. It is concluded that natural disasters is an important determinant of migration from SSA. The findings in this paper imply that global climate change, through leading to more extreme weather events, will contribute to further migration from the continent.
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According to different statements more and more youngsters, under 25 years of age, appear in Public Work Programs at the present time in Hungary. Even it occurs more frequently that parents, primarily because of financial reasons, take out their children from school, and send them to public workers.This paper draws attention to this phenomenon. Furthermore, it shows a possible parallel between those young people who are in JWT (Job Without Training) and those Hungarian youngsters who are working in Public Work Programs reflecting on the Hungarian particularities of this parallel.The concept of JWT and its categories are presented, and also which of these categories may connect with the Hungarian public workers’ state of being. Statistical data show the rate of public workers and their gender breakdown. Reports also suggest that the rate of young public workers is growing and their situation may become futureless.The author thinks that the growth of young public workers’ rate and their settled situation in this employment sector is likely to make inevitable for them to become NEET in the future.
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The aim of this study is the analysis of the public opinion on the construction of nuclear power plants, which is a hot topic in Turkey recently. We also aim to interpret the results obtained by using scientific methods. A questionnaire survey has been prepared about public opinion on nuclear power plants. Alternatively Computurized Argument Delphi Method is utilized for the problem, which allows people to make dialectical discussion about the same subject of the survey. This paper discusses the results and considers the Computurized Argument Delphi Method as an alternative of questionnaire studies.
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Allelopathy describes plant-plant interaction by chemicals released into environment. In most cases negative effect of allelochemicals is detected due to their toxicity. L- canavanine belongs to the group of non-protein amino acids, and is known as antimetabolite of L-arginine. L-canavanine is synthesized in legumes. It functions as a putative source of nitrogen, and is famous for its insecticidal activity. The work summarizes the current knowledge on the role of L-canavanine in plant metabolism and their impact on growth and development of plants. A special attention was pointed also on L-canavanine in plant-herbivore interaction.
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Bioremediation is biological technology of removing chemical substances of different kinds from soils, bottom sediments, active sediments, water, and air. It utilizes capability of living microorganisms, which can catalyze, destruct or transform various types of pollutants, into less harmful forms. Unfortunately, many substances can act as a contamination introduced into the environment causing ecological imbalance or disappearance of different trophic levels of the food chain. Bioremediation uses natural ability of microorganisms to degrade hydrocarbons. The main objective of this process is the mineralization of toxic organic compounds, leading ultimately to the formation of non-toxic substances like CO2, H2O and biomass. Hydrocarbons, such as derivatives of petroleum, in metabolic transformation of microorganisms constitute their carbon and energy sources, and can act as an acceptor of electrons. However, the rate of utilization of above-mentioned substances by microorganisms depends largely on the chemical nature of substance being degraded, as well as environmental factors, which can stimulate or inhibit these processes.
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In this study, Körfez (Kocaeli) coastal zones due to pollution, salinization of aquifers in order to determine the electrical resistivity method is applied. In practical work, the presence of saline zones near shore areas can be clearly seen. This salinity zone is to penetrate into fresh water aquifers by moving in the direction perpendicular to the coast. This saltwater intrusion is inclined in the direction of the coast from the seafloor. Hydro-static pressure due to static water level continues to lower the salt zone's progress. During the field studies, the resistivity profile cross-sections taken in the vertical direction; 62-94 Ω m in shallow are as like values were observed. This value for the fresh water aquifer is seen in the normal range. In contrast, a sudden drop in altitude decreases the sheet resistivity values were observed in the vertical direction. Research in the field of 2-4 Ω m show value of resistivity in the vertical direction and zone of salt water intrusion (intrusion) shows that progress. The proposals presented in the results of the research, the technique of drilling, underground basins are expected to contribute to the use and management issues.
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In 9 sites of Hedera helix occurrence were recorded in the forests surrounding area Szadek. The species grows mainly on the fresh-mixed and – fresh forest site types. 195 flowering and fruiting specimens were found. The most frequent support for Hedera helix offer such tree species as black alder Alnus glutinosa, common oak Quercus robur and Scots pine Pinus sylvestris. Flowering specimens of the climber are found growing at forest edges, in degraded communities of mixed linden-oak- and -riparian forests as well as in the fringes of gaps in forest stands under reconstruction. The dispersal of Hedera helix in forests is attributed to both the rise in annual average temperatures and, in particular, higher average temperatures in winter months, and to the fragmentation of forest.
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U kontekstu sagledavanja ekološke krize, kao velikog svjetskog problema, kultura dobiva sve veći značaj, jer uključuje univerzalni odnos Čovjeka i Prirode, cjelinu oblika življenja i djelovanja koji imaju društveno-ekonomske uslovljenosti, specifičnosti i zakonitosti koje se, nesumnjivo, manifestuju i na kvalitete prirodne okoline. Međutim, izraženi i učestali zahtjevi za tolerantnijim odnosom prema izvanjskom, prirodnom često se svode isključivo na dobru volju i ponašanje individue, što smanjuje opšti pojam kulture i sužava njen udio u savladavanju i ublažavanju ekološke krize.
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The object of my study is to analyse the representations of former smugglers in the border forest area, which directly affected the nature of the work they performed. By the analysis of the empirical material through the theory of ecological anthropology, I will refer to the classification of the area indicating the nature of the relationship between man and environment. The classification of this area is the proof, that environment and human exist in mutual interaction and significantly influence one another, they cannot be perceived as separate or contradictory facts. The perception of this environment primarily depends on the actions former smugglers carried out in this area and it is also shaped by how the environment influenced the bearers of studied representations.
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The article focuses on two research laboratories at the University of Žilina in University Science Park under the names “Modelling and simulation of crisis phenomena in the transportation to increase the efficiency of decision-making process” and “Research systems for protection of critical infrastructure objects in the transportation”. Respective parts identify the main goals of the research, research focus and the uniqueness of respective laboratories as well as practical application within University Science Park of the University of Žilina, the Slovak Republic, the EU and the world.
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The paper is related with tends to elucidate various forms of harm generated by space pollution to economy of the region in context of the ideas of Agenda 2000 etc. The study discusses the data of the air pollution and subsequences of damages that are fixed in elements of high-rise metal structures. It adduces some data of factual pollution that is dangerous to high-rise metal structures, location of initial generators of pollutants, interrelations of polluted flows during their migration in the air. Experimental observation reveals the accumulation of micro and local defects, and their joining process. Afterwards aftereffects are discussed as stress concentration around defects, wear and tear of structures, the scattering of strength resources, loss of the durability of single element and the structure in whole. The residual strength of steel elements of structure was tested using standard specimens that had been cut out from the elements of structure at the end of its exploitation.
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Alkali activation is a highly active and rapidly developing field of activity in the global research. Alkaliactivated cements have found a variety of applications: transportation, industrial, agricultural, residential, mining and so on. Alkali activated binders are made by mixing industrial aluminosilicate waste materials such as one of them is slag. This study aims to evaluate the influence of incorporating aluminum hydroxide on the physical and mechanical properties of alkali-activated slag. Mineralogy of composites were studied using X-ray diffraction analyze. The results showed that the molar ratio of raw materials strongly affects the kinetics of reaction and the structural evolution of the solid phases forming in alkali silicate activated binders. The role of Al(OH)3 in the mixtures in activated binders is closely related to the availability of Al in the system, because it controls the concentrations of secondary products such as zeolites. Based on the experimental results, it can be concluded that by reducing Al2O3 from 1.30 mol till 0.75 mol (in the mixtures of raw materials) the compressive strength of samples increases from 27 - 42 MPa till 39 - 54 MPa.
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Concrete – composite material which economical effect mostly depends on the amount of binder material (usually cement), its type and fineness. Cement manufacturing generates great employment of energy resources. The demand for all kind of manufacturing natural resources are aimed to be reduced as much as possible. Alternativeraw material resources are being introduced and tested together with increasing self-compacting concrete (SCC) popularity in Lithuania. Considering environmental requirements to reduce environment pollution according to ES 305/2011 regulation and importance of economic benefits it is aimed to investigate recycled concrete influence for self-compacting concrete durability properties. Assessing one of the main mechanical concrete property – compressive strength up to 1 year concrete hardening duration, it was observed, that replacing cement by concrete dust, practically no negative influence was observed. In some cases this replacement even improves concrete compressive strength (10 % concrete dust), except greater amount of additionally grinded concrete dust. In our case it was noticed, that replacing up to 10 % cement by concrete dust from 1.85 % to 2.09 % increases concrete closed porosity and predicted concrete resistance to freeze-thaw cycles increases up to 30 %. It allows to expect positive test results while real test would be carried out on the basis of Lithuanian standard LST 1428.17.
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The historical view of sewage and rainwater cleaning, possibilities of applying it nowadays and newest experience in the world are analyzed in the article. The main advantages and disadvantages of the system were revealed after research. There were two parts of the analysis: personal cleaning and territorial planning. Biological and mechanical filtration were mostly used types of water cleaning. Main problems of ecological cleaning and reusing of wastewater were found: rather high price, possible permanent damage to the soil.
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Coconut shell being a hard and not easily degradable material if crushed to size of coarse aggregate can be a potential material to replace coarse aggregate in concrete. In this study the characteristics of the coarse aggregate and the coconut shell were evaluated. Properties of fresh and hardened concrete with partial replacement of coarse aggregate with coconut shell were also studied. Concrete specimens with 0%, 5%, 10%, 15% and 20% by weight of coarse aggregate replacement with coconut shell were made at 1:2:4 mix ratio. The compressive strength for all the concrete specimens was evaluated at 7, 14, 21 and 28 days and constant water cement ratio of 0.5 was maintained for all the concrete specimens. The aggregate crushing value of the coarse aggregate and the coconut shell were 23.47% and 28.25% respectively and the aggregate impact value of the coarse aggregate and the coconut shell were 17.44% and 20.2% respectively. The slump values, densities and compressive strength of concrete decreased as the percentage replacement with coconut shell increased. Concrete produced with 0%, 5%, 10%, 15% and 20% replacement attained 28 days compressive strength of 38.17, 35.11, 32.14, 31.18, and 29.14 N/mm2 respectively. The results obtained in this study showed that coconut shell satisfied the requirements for coarse aggregate and can be used as partial replacement of coarse aggregate (up to 20%) in concrete pavement production.
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