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thermal efficiency enhancement reaches 15% using Ag–MgO/Syltherm 800 under high concentrations. As it can be seen in the previous section, researches on the effect of using hybrid nanofluid in the PTC did not take a high interest in comparison

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between 20 and 60% for the bed depths of 5–15 cm. Salman J. M. and Hameed B. H. [ 13 ] performed adsorption of 2.4-Dichlorophenoxyacetic acid (2.4-D) and Carbofuran on GAC F300. The initial sample volume was set to 200 mL with concentration ranging between

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will play a vital role as a cementitious material due to the high concentration of lime and gelignite. On the other hand, because of the problems, which are occurred in the subbase layer in roads and buildings in Iraq, many ways can be adopted to

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The analyzed samples were runoff waters from bituminous roofing. The runoff water pH was lower than that of the storm-water. First flush phenomena were observable in the samples conductivity, turbidity as well as suspended solid, dry and organic matter concentration. The reason of the phenomena is the initial dissolution of deposited aerosols and weathering products. Because of that, the roof runoff quality is affected by the dry period length. Presumably to the roof matter, the samples had high dissolved organic matter concentrations. The measured polycyclic aromatic hydrocarbon (PAH) concentration implied the dissolution of some component from the roof matter.

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Abstract

This paper is about comparing the effectiveness of the sorbent materials of granulated activated carbon in removing of bromates from drinking water. The limit value (10 µgl−1) of bromates in the drinking water was stated by World Health Organization. In order to insure the reduced concentration of bromates in the drinking water, an experiment was performed using the batch test. In this experiment different types of sorbent materials with different properties were testing. Based on batch test were measured the parameters like the immediate adsorption capacity, the adsorption efficiency, and the concentration of bromates after the adsorption were measured at the evaluated time.

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Abstract

The main goal of this study is firstly to model the phenomenon of advection and diffusion of the gaseous residues of coal combustion. On the other hand, to study the dispersion of this pollution by varying the parameters like the wind and the resources of pollution, where there are four emissions: SO2, CO, NO2 and PM10. The present model will compare estimating concentrations with the results found by the contribution of the thermal power plant of Jerada city, where the American Environmental Regulatory Model is used. The results suggest that SO2, PM10, NO2 and CO concentration simulated by turbulent k-ε model in combination with the transport model of diluted species, at the 3h and 24h intervals, greater than their respective observed concentrations compared with the American Environmental Regulatory Model. The concentrations of the model found are very high and exceed the limit values under the study conditions. Indeed, the simulated model was used in 2D with a very low wind speed (10−4 m/s) and in the absence of gravity, hence the total neglect of altitude because the two sources of pollution are at the height of 120 m.

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/4 807 812 Dragun Z., Roje V., Mikac N., Raspor B. Preliminary assessment of total dissolved trace metal concentrations in Sava River water, Environmental Monitoring and

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The adsorption properties of natural zeolite (clinoptilolite) has been studied in order to determine its applicability for copper and zinc removal in acid mine drainage treatment process. For purpose of these experiments the determination of the sorption equilibrium and removal efficiencies were performed under batch conditions using single and dual-component solutions. The experiments were carried out under acidic conditions (pH approx. 4). In general, the obtained results from kinetic experiments showed rapid decrease of the metal concentration during the first 10 min, corresponding to ~80% total removal of ions from both single and dualcomponent solutions. This initial rapid period was followed by a further slow drop in metals concentration caused by ion-exchange in deeper structure of zeolite.Preliminary tests on the real samples of acid mine drainage from Smolnik mine, Slovakia, showed that natural zeolite has a potential as an alternative low cost adsorptive material for acid mine drainage treatment.

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Road traffic flows in intersections are modeled in this article. Cost of CO2, CO, CH, NOx, PM and value of travel time have been used in order to estimate the social costs arising at the intersections. The article presents assumptions for constructing the mathematical model, it describes the mathematical model and gives simulation results. Traffic flow parameters, as traffic flow concentration and traffic flow speed are presented as based on real traffic data.

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Pollack Periodica
Authors: Kalman Buzas, Peter Budai, and Adrienne Clement

One and a half year long field sampling was established in order to evaluate the contamination of storm water runoff. The event means (EMC) total petroleum hydrocarbons (TPH) concentration of the runoff was a function of the actual traffic intensity and the rainfall depth. It was concluded that this TPH, of which dominant component is the engine-oil (characteristically C28) does not form an ‘oil-in-water’ type emulsion in the condition of normal motorway-operation, but is interlocked to asphalt, rubber and soot particles of maximum some ten microns size. This condition influences the possibility, way and extent of separation alike. The separation equipments and their sizing applied so far are not suitable to achieve efficient surface water protection. Practical prevention method of accidental type environment pollution was also suggested. On the basis of the international literature evaluation, technical solutions capable to decrease the runoff pollution were summarized. Among these, useful calculation method was developed for designers to determine the sufficient storage capacity (water quality volume) of reservoirs applied for water quality protection. Monitoring technique of runoffs, which are characterized time dependent, variable pollutant concentrations by their nature, was proposed. It was stated that the administrative regulation should aim at the EMC instead of current concentration. Beside TPH information was gained on polycyclic aromatic hydrocarbons (PAHs), suspended solids, heavy metals, pH, and nutrient (N, P) pollution of the runoff, which are valuable for the grounding of further research results.

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