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Abstract  

Measurements of radon in potable mineral waters along the Cota Mil Highway at two sites, La Castellana with five sampling points within 20 meters of each other and two collection points at the San Jose site were carried out from November, 1997 to December, 1998. Temporal radon variation patterns will be presented for the seven sampling points, which had very different water flow rates and short-term variations. The extraction of the radon from mineral waters was accomplished in the laboratory a few hours after sampling and the measurements were performed employing a radiation monitor with a scintillation cell 18 hours latter to insure that the radon and its decay products were in equilibrium. The results suggest that the increase of radon from the middle of February to the middle of November can be related to the decrease in atmospheric temperature and rainfall. The large differences in the minimum and maximum values of radon and the short-term variations show the need for many measurements over a year to quantify a correct annual value to be employed in dose calculation for radiological impact studies on human health. Finally, we have also concluded that water sampling points with very low water flow rates are more suitable for investigating the possible relation between radon anomalies and seismic events.

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Abstract  

Radionuclide X-ray fluorescence method with Si/Li semiconductor detector and238Pu exciting source was used for the determination of Cu, Ni, Zn and Pb in plant samples (Taraxacum officinale) from various localities near the highway D-61 Bratislava-Trnava (SR).

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Abstract  

Radionuclide X-ray fluorescence method with Si/Li semiconductor detector and238Pu exciting source was used for the determination of Cu, Ni, Pb and Zn in soil samples from various localities near the D-61 Bratislava-Trnava highway (SFR).

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Abstract  

An approximation of the distribution of lead particulate from vehicular exhausts is given. A neutron activation analysis study has shown that there is an extremely detailed pattern of the effluent from vehicular highway traffic.

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Abstract  

Exhaust systems of modern cars contain catalysts for the reduction of CO, NOx and hydrocarbons. These catalysts are made of ceramic materials with a large surface on which platinum metals catalyse the oxidation. The catalysts contain approximately 2 g of platinum and 0.4 g of rhodium. Recently platinum is being replaced by palladium. During driving the platinum-group elements (PGEs) are expelled from the tip in fine particles and are deposited in the environment. For a projected study of emissions from cars driven on streets and highways it is important to know which elements can be measured by short time activation analysis without any chemical procedure.

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to the temperature range use at the pavement, high resistance to fatigue and to thermal deformation. Certainly improvements in paving roads and highways will have a direct impact on reducing the number of accidents. It is worth mentioning that

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Agrokémia és Talajtan
Authors: I. Potyó, I. Kása, Cs. Farkas, Gy. Gelybó, Zs. Bakacsi, M. Dencső, E. Tóth, and Á. Horel

. 2445 – 52 . Hill , B.R. 1996 , Streamflow and suspended-sediment loads before and during highway construction, North Halawa

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-011-1531-8 . 5. Brown , PW , Shi , D , Skalny , JP 1993 Porosity/permeability relationships concrete microstructure porosity and permeability Strategic Highway Research Program, NRC Washington, DC 43 – 75

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. Irodalom A LLEN , M. F. , 2007 . Mycorrhizal fungi: highways for water and nutrient movement in arid soils . Vadose Zone Journal . 6 . 291 – 297

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1. Mackenzie , RC 1974 Highways and byways in thermal analysis . Analyst 99 : 900 – 912 10.1039/an9749900900 . 2. Publications of RC. Mackenzie

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