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This paper summarizes the results of laboratory experiments of the gasification process of waste polymers, with particular focus on monitoring the quantity and character of the resulting solid, liquid and gaseous products . Input materials such as tires, PC components, CDs, and tire mixtures with HDPE and PET were selected. The gaseous products were analyzed by gas chromatography, which were monitored following components: methane, ethylene, propa ne, carbon dioxide, carbon monoxide and hydrogen. From the analysed...

Within the NATO Science for Peace Project 981882 “Site-effect analyses for the earthquake-endangered metropolis Bucharest, Romania” we obtain a unique, homogeneous dataset of seismic, soil-mechanic and elasto-dynamic parameters. Ten 50 m deep boreholes are drilled in the metropolitan area of Bucharest in order to obtain cores for dynamic tests and vertical seismic profiles for an updated microzonation map related to earthquake wave amplification. The boreholes are placed near former or existing seismic station...

Bacterial density, biomass, morphological dive rsity and cell integrity were studied in surficial sediment samples taken form eight locations on the Romanian coast. Investigation was done by epifluorescence microscopy, employing SYBR Green I (universal fluorochrome) and propidium iodide (for visualising cells with damaged membranes). Cell density varied between 4.62-9.64 Г— 107 cells/cm3 sediment, showing a relation to sediment grain size. Dry biomass ranged between 3.03-6.39 Вµg/cm 3. Rod shaped bacteria were dom...

In the article is a brief description of the methods of thermal analysis, description of bentonite deposits and treatment of this ma terial. Also, this te xt is discussed the practical application of thermal analysis to evaluate materials that can be reused as secondary raw materials in various industries. This method allows both quantitative and qualitative evaluation of a sample. Examples of such material may be bentonite, its evaluation of thermal analysis is presented in this article.

This paper represent a short review of non-metallic resourceses (NMR) on few selected lignite deposits in Kolubara Coal Mines (KCM) and estimate thems potential in material and economic aspects. The further discussions are in preliminary mean and looks like an preliminary case study estimation. The paper is in agrement with the principles of sustainable development and the principles of complete and complex utilisation of mineral resourceses potential of the coal deposits. A timing of open pit works on ’’E’в...

The paper deals with the issue of separating biodegradable PLA (polylactic acid) bottles from conventionally used packaging materials such as PET (polyethylene terephthalate). The separation of these materials is especially important because each of the plastics has a different cycle at the end of its secondary use. Recycling PET bottles the quality of the granulate may be degraded due to the occurrence of PLA material, while the occurrence of PET is undesirable during composting the biodegradable plastics PLA as ...

The objective of the work was a laboratory examination of biodegradation of sewage sludge from the Central Wastewater Treatment Plant (ГљДЊ OV) in Ostrava, which had undergone physical pre-treatment by means of a spark discharge or UV radiation. The laboratory tests made use of a bacterial mixture of Rhodococcus sp. and Pseudomonas putida.

The soil represents a triphasial poly-disperse system that can provide thriving conditions for various groups of invertebrates: aquatic organisms (protozoa, certain nematodes, rotifers) evolving in soil’s pores water f ilm, aerobic organisms (microarthropods) living in well aerated interstitial spaces with water saturation and m acrofauna (insects, larvae and lumbricidae), all generating a strong impact upon soil’s phases. The last two categories develop the greatest impact, thus their evaluation becomes of gr...

Biosorption of Cd(II) ions from aqueous solu tions has been studied and determined to adsorption capacity. The expe rimental data obtained from batch equilibrium tests have been analyzed by three two-parameter (Fre undlich, Langmuir and Temkin) isotherm models, four three-parameter (Redlich-Peterson, Sips, Toth and Khan) isotherm models and kinetic models including the pseudo-f irst order and pseudo-second order. The adsorption data fit well with Temkin isotherm for orange peel and Freundlich isotherm for walnut a...

Main goal of our research is to find some way how to help colour blind people to distinct the entities with differe nt colours. So far it is impo ssible to develop some kind of device or computer algorithm to let the colour blind man see in the same way as healthy man. So, we try to transform pictures (both static pictures and dynamic pictures from computer camera) to let the person with diagnosed colour deficiency see there as many details as possible. Algorithm that we have researched deals with transformation o...

Gravity which is the basic potantial, can be used in geodesy, geology and other field of engineering. In order to portray earth surf ace, geoid is needed which is the shape of globe and tranquil sea surface lands are believed to keep on under them. In order to determine the geoid, gravity should be k nown. Corrections for the gravity value differences sourced by gravity values, whic h are measured on earth surface, should be done that these corrections are called as gravity reducing. In this study, and latitude an...

The issues in assurance of energy sufficiency and of environment quality are necessary part of scientific prognosis humanity evolution. The buildings belong to major consumer non-renewable energy and are emitter of greenhouse gases and other gaseous wastes during whole life cycle. The CO 2 emissions mostly come from the energy required to heat, cool and ve ntilate buildings. There are al so significant emissions from creating the materials to build, maintain and demolish buildings. Climatic changes, increased poll...

For mining support made of monolithic conc rete required additional application of solutions to improve the stre ngth characteristics. These solutions lead to high lift bearing capacity of the mining support conc rete. The transmission coefficients method is a method of computing tasks of monolithic c oncrete support, support that come in the contact with the massive rock. By the method of transmission coefficients of the tasks are taken into account various types of actions, namely the action given by the weight ...

At fire there are formatted many of co mpounds by the decomposition and oxidation reactions of fuel. Some of these compounds have a negative impact on environment. A various mixture of toxic a nd non-toxic substances we can determine at burning of synthetic polymers. There are present di fferent carbohydrates and their derivatives except carbon oxides and water. The composition of smoke is influenced by fuel characteristics and also by burning c onditions (mainly oxygen concentration and temperature). The analyses...

PIC has been started to be used widely in the field of industry and industrial electronics. To the effect that, in place of highly complex systems such as relay contractor, timer, etc, can be controlled by this microcontroller which consists of all. Within the context of this design, broad information is given on pneumatic component which has a major place on automation industry and PIC. In this presentation, information is given on Pneumatic carrier system and components. In addition to this, step motors, their s...

The production of pulps and paper has a variety of negative influence on the environment. There are some technologies which can moderate the negative impacts and they have also a positive economical ef fect (e.g. paper recycling). It causes the paper alterations, which results in the degr adation of their physical and mechanical properties. The recycling causes a chemi cal, thermal, biologi cal and mechanical destruction, or their combination. The aim of this work was to investigate changes of macromolecular weigh...

The research done by the climatology specialists of the National Meteorology Administration, using long stri ngs of data collected from 14 meteorological stations, showed, on a national level, an average temperature rise of 0.3В°C between 1901 and 2000 and of 0.5В°C between 1901 and 2007, which is statistically relevant in the Carpathian region, with certain seasonal os cillations. The data analysis done with the help of the archives gathered from a la rge number of meteorol ogical stations (94), consisting of con...

The biggest polluters of water resources are industrial waste water produced after various production technological processes. Within the industrial complex RTB Bor, the waste water are generated during the copper production process with negative impact on the environment, reflected in long-term contamination of soil with which they come into contact and accumulation of heavy metal ions in it, in inflow into surface water and mixing with ground water and their pollution. Directly, the most vulnerable are the Bor R...

Science, Engineering and Technology (SET) interests among young people has to be raised gradually. Incremental building of SET image for young people means employing several tools. One of them is educational background to be perceived by future students as attractive. This perception was observed in two case studies at secondary schools of technical and non-technical programe. It was the aim of the survey to gather and analyze the data about the perceptions concerning the SET issue. The objects of interest had bee...

The Romanian coasts can be divided in two categories: erosion coasts (cliff shores) and accumulative coasts (barrier beaches). The activ e behavior of the cliffs is due to the action of marine abrasion and slope processes, landslides and gravitational collapses. Cliff shores between Cape Midia and Vama Veche has a complex lithological profile. Silt and clay particles are carried seaward by the rip cu rrents system, while sand and gravel particles are conveyed along the coast. Textural and mineralogical study of th...

Urgent task of energy policy in the near term, in addition to diversification will encourage vigorous national economy, reducing dependence on natural gas and both demand-side measures (in the energy supply of buildings are mainly to improve the thermal protection) by measures on the production, transmi ssion and distribution (increasing efficiency of energy transforma tion and increasing the share of renewable energy at the expense of natural gas).Natural gas can be easily replaced in the supply heat buildings, a...

The paper presents the results of column adsorption of Cu 2+ metal ions from synthetic solution (concentration up to 200 mg dm -3) onto beech sawdust and wheat straw. Adsorption ability of the chosen type of adso rbent is considered as a function of the initial pH of solution. The breakthrough curv es are presented as a function of the aqueous phase volume passed through the colu mn allowing getting an insight in the column adsorption features. A very high adsorption degree – higher than 99% was achieved in thes...

Some renewable energy sources, such as biomass, hydro, geothermal and tidal energy, produce reliable electricity, which can be distributed to remote locations. Other sources, like solar and wind depend on the weather, but it is predictable and so their usefulness may be suitably amended with permanent renewable energy sources. The vast majority of renewable energy in add ition to their advantages in terms of their source inexhaustibility also has significant drawbacks which significantly limit their expansion. For...

Mining and Metallurgy Institute in Bor, Se rbia, has successfully dealt for many years with processing of precious metals. Platinum and palladium have originated from the raw materials of the Bor deposit. By furt her refining in the Institute, the mentioned platinum metals are transformed into high-pu rity metals of which products for various purposes are manufactured. This paper presents the results of comparativ e analysis the high temperature strength of platinum and palladium. The limit of tensile strength as ...

With climate change in recent years, tourists, whether foreign or domestic would prefer to assess the danger associated to some locations they visit. In this paper the analysis of temperature was preferred, because it represents the most accessible type of data for long periods, and for statistical analysis. The studied region, the Eastern Carpathians is considered as one of the coldest part of Romania, but also a touristically attractive region. We selected for analysis three majo r basins (Giurgeu, Ciuc, Intorsu...

The process of Environmental impact assessmen t (EIA) is successfully applied as a tool for environmental planning and environmental policy in many countries worldwide. It is generally accepted that the environment has three inter-dependent components: economic, socio-political and natural. C onsequently, integrated environmental assessment and management coupled with su stainable development is critical, and in order to achieve this goal, effective guidelines and implementable legislation are necessary. EIA legis...

In 2010, in Romania, was made measurements of declination, inclination and total magnetic field. First of all we analyzed differences between the data measured by us and IGRF 11 (International Geomagnetic Reference Field 11). After the general view of vertical geomagne tic field anomaly in Romania resulted from measurement in 2010 with the comparison of the IGRF 11, in the end we show a study in the Bacau area (about 600 km2).

The Moravica River is one of the most signifi cant right tributaries of the South Morava River. Its total length is 43 km and basin area 640 km 2. The municipal center of Aleksinac with its urban, commercial, industrial and cultural areas is situated close to the Moravica river estuary in to South Morava river. Due to position of the settlement and the natural river channel conditions, significant damages occurred in the past. Flood flows were endangering the inhabited part of Aleksinac, residential and public str...

It is introduced a complex approach for texture and multispectral segmentation, based on texture analyses. The data fusion method is used for combining the multispectral and texture features of classes in the area s which is investigated. The texture features are estimated by the calculation of variance and skewness statistics over the windows with different sizes. The results ar e integrated with spectral chan nels of satellite images. The images from KOMPSAT-2 satellite are used for testing purposes. The spectra...

This paper aims at studying some complex coagulants derived from the medium anionic polymer and medium cationic surfactant in order to evaluate the opportunity to use them in destabilizing and removing th e colloidal systems from water and wastewater. In this respect, medium anionic copolymers of acrylamide and sodium acrylate with commercial Preastol 2540, and a medium cationic surfactant derived from triethanolamine with commercial name of Tetranyl AT-7590 were used in order to obtain these complex coagulants. T...

The hydrometallurgical process for obtaini ng alumina by Bayer process bauxite is getting significant amounts of red mud (0.8 - 2 t / t Al 2O3). It is deposited in dumps which can cause danger for environment mainly due to the alkali content ( pH = 8-13) and small dimensisons of particles (less than 60 microns). Chemical and mineralogical composition of red mud bauxite is closely related to type of the bauxite used as raw material and processing conditions determined by some peculiarities of applied technology (pr...

On global scale the nickel coa tings obtaining is realised with electrolytes that have the toxically composition that working at the temperature range 40 - 800C. In this paper was proposed an ecological solution to obtaining the nickel layers and composite coatings with nickel matrix and silicon. The energy consume is reduced be cause the working is passed on ambient temperature. The addition of silicon particles into nickel plating bath leads to significantly changes for the surface morphology and for the roughne...

The modern approach of the water removal works, in sustainable water management conditions, assumes the use of information technology. A series of new methods developed in the frame of computer aided design field have as results the increase of the quality in research and design activitie s by enlarging and studying throughly the scientific investigation. Th e specialized software programs allow to choose and check all the hypothesis assumed, to simulate th e processes and see in a dynamic way the answers to the c...

The favorable geographic conditions, in direct relation with the variety of the natural resources have contributed to the development of the rura l settlements and of a certain specific type of economy, in the Subcarpathian area of Dambovita Valley. The agricultural activity now holds an important role in the economy of these human settlements, a fact demonstrated both by th e proportion of the population employed in agriculture and by the land use changes. During the last decennia, the wood exploita tion and proc...

The cooper ore reserves of Ro Еџia Poieni deposit (Romania) represents about 40% of the national cooper ore, that importance increasing with the actual rising cooper price on the international market. Deposit mineralization is located within the Fundoaia andesitic ore body and appears mainly on a system of fractures, or as uneven distribution impregnations in andesitic rocks. The mini ng of this cooper deposit began in 1977 and in 1985 reaching about 9 million tonnes of or e capacity and in 1988, 15 million tonnes...

The research regarding the soil pollution with fluorine has been realized on the lands near the Aluminium Factory from Slatina (S .C. ALRO S.A.). Two soil profiles (0-120 cm.), as well as several agrochemical proofs (0–20 cm.) from the area that has been the most affected by pollution have been analys ed (Picture 1). Fluor ine accumulations in soil occur depending on the emissions intensity , the atmosphere status (the prevalent direction of air stream s, the frequency and the quantity of the rain-fall), the dis...

Here we try to find a compromise way of controlling a continuous variable power system by adopting a hybrid architecture in which the renewable energy sources are coupled with the classic power grid. In such an architecture, a big issue is the control algorithm for management of the energy sources, which had to be designed in such a way that the final consumer remain powered on at all times. We proposed a control algorithm which compares the input and output powers, if the input power is lower than the output, the...

The main aim of this work is to study the recovery of copper sulfate from mine waters at the Mining Company Bor. For the copper sulfate recovery was treated 91 m 3 Underground mine water, containing 0.3 g/l copper, 2.2 g/l iron at pH 3.2 and 37 m 3 Cerovo mine water, containing 0.5 g/l copper, 0.61 g/l iron at pH 4.5. The mine waters were mixed and prepared 128 m 3 mine solution (copper content 0.35 g/l, iron 1.74 g/l, pH 3.8), then are pre-treated chemically a nd physically for recovery pregnant solution. The fir...

Territory of the Republic of Macedonia, as a part of Balkan region is characterized with a high seismic activity. Current seismic activity indicates that the tectonic processes are very intensive. Epicenters are not equally distributed in the region and are grouped in three different zones: 1) Drim zone, 2) Vardar and 3) Struma zone. First zone is situated on the west, on the Albania border, i.e. with profound fault in the border section of the Western Macedonian zone with the Merdita zone in Albania, known as Dri...

Often manufacturing and preparation of samp les for geomechanical characterization is expensive and time-consuming and energy, and estimate various properties can be made by using empirical correlations. As part of the geomechanical characteristics of rocks are closely linked, can achieve a quantit ative and qualitative an alysis using the correlation functional relationships that can exist between physical properties, strength and deformation. Correlation between rock properties relationships have been establishe...

Contribution mentions reasons for rising of rusting and incrustation and possibilities of its removing at the technological equipments during using of hot geothermal water. Biggest attention is given to the choice of me thods for treatment with geothermal water, either by chemical or by physical way and further attention is given to the geothermal energetic system and its parts that are subjected to the rusting and incrustation.

The Dardanian zone (Serbian-Macedonian massif) represents the western part of the Rhodope crystalline basement. This zone was structured and metamorphosed during the Hercynian and post Hercynian tectonic st ages. The geological mapping at 1:25.000 [1] show that a of the studied region is built of crystalline Pale ozoic basement. The important aspects have been identified in the structure and metamorphism from this part of western Rhodopes. The study of the deformed Variscian and Hercynian tectonic phases are diffi...

A database of average monthly air temperat ure and atmospheric precipitation has been created for seven meteorological stations for the period between 1936 and 2009. It was used to study current trends of climate change in the Kazbegi area, a mountain region in the Greater Caucasus. Changes in temper ature and precipitation are described by circular regression equations and rates of these changes are identified.

Geostatistical analysis provides a powerfu l tool for enhancing the prediction and decision making capabilities of geologists and mine planners. The majority of practicing geologists are involved with mining and/or exploration ventures. As such a significant proportion of the geologist’s time is devoted to designing and impl ementing drilling and sampling progr ammes and using the resultant data to predict (and reconcile) reserve tonnages and qualities on a variety of scales, ranging from life-of-mine areas to d...

Transport noise barriers are ecological struct ures that are designed and built along the roads (motorways, expressways and railways etc. ), in order to reduce the noise levels to the limit values for urban areas and in rooms of buildings. Assessment of the effectiveness of the barrier is carried out th eoretically, empirically or by a combination of both methods. To automate the design of th in noise barriers are created four modules from the series Screen *, which are part of the software package for acoustic ca...

Concrete and mortar made with Portland cement can be damaged when exposed to solutions containing sulphate. Waste water ofte n contains sulphuric bacteria, and so the piping is frequently damage due to sulphate attack. In case of concrete sewer pipes this phenomenon is caused mainly by the sulphur-o xidising and sulphate-reducing bacteria that are forming part of the biological circulation of sulphur and its compounds in biosphere. These bacteria take part in the dissimilatory part of this cycle and the bacterial ...

The definitions of the risk factors due to a possible earthquake on the settlement area are useful for decreasing hazard of a potential earthquake and essential for preparing the management plans by the local municipalit ies and government. Soil amplification, vulnerability of buildings, natural period of soils and liquefaction are the main risk factors of a possible earthquake. On the othe r hand, before definitions of these risk factors, the distribution of the soil classe s should be determined. By the way, the...