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Monika Śleziak and Marek Duliński

and by-products. Health Phys ., 48 , 87–95. 12. Yu, K. N., Guan, Z. J., Stokes, M. J., & Young, E. C. M. (1992a). The assessment of the natural radiation dose committed to the Hong Kong people. J. Environ. Radioact ., 17 , 31–48. 13. Central Laboratory of Radiation Protection. (2006). Radiological atlas of Poland 2005 . Warsaw: CLOR.

Open access

Sylwia Kaczmarek

postemergence herbicides]. Fragmenta Agronomica 30 (1): 62–68. (in Polish, with English abstract) Kaps M.L., Ondea M.B. 1994. Split and tank-mix preemergence application of herbicide for controlling weeds in grapes. HortScience 29: 619–620. Knezevic S., Evans S., Blankenship E., Van Acker R., Lindquist J. 2002. Critical period for weed control: The concept and data analysis. Weed Science 50 (6): 773–786. DOI: 10.1614/0043-1745(2002)050[0773:CPFWCT]2.0.CO;2 Księżak J., Bojarszczuk J., Staniak M. 2012. The productivity of maize and sorghum yields of according

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Janusz Datta and Józef Haponiuk

Advanced coating of Tank Interior as means of Rising Environmental Safety of Tankers/RIM technology

The application of Reaction Injection Molding (RIM) technique for forming an elastic polyurethane coating that displays selected strength characteristics, and chemical and thermal resistance is described. The study was conducted on technical-scale using a mixing-dosing device that allowed direct dosing of liquid polyurethane system into the steel bulkhead, onto the steel surfaces, and the formation of polyurethane coating. Hard coating formed after polymer gelation and crosslinking. The elaborated technology also allowed joining of ceramsite concrete which resulted in the sandwich costruction consisting of steel, concrete and polyurethane.

Open access

Gopi Solaiappan, Ganesan Singaravelu, Aruna Prakasarao and Sanjay Supe

Comparision of beam data requirements for MLC commissioning on a TPS

The treatment planning system (TPS) has become a key element in the radiotherapy process with the introduction of computer tomography (CT) based 3D conformal treatment planning. Commissioning of a MLC on a TPS either for conformal radiotherapy or intensity modulated radiation therapy (IMRT) requires beam data to be generated on a linear accelerator. Most of the TPS require these beam data to be generated with routine collimator jaws. However some TPS demand the data to be provided for MLC shaped fields. This prompted us to investigate whether beam data with jaws differ than that with MLC and whether the jaw based beam data would suffice for the commissioning of a MLC on a TPS.

Beam data like percentage depth dose (PDD), cross beam profiles and output factors was acquired for jaws and MLC defined square fields for 6, 10 and 23 MV photon beams. Percentage depth dose and cross beam profiles were acquired with a radiation field analyzer RFA-200, CC13-S ion chambers with active volume of 0.13 cm3 and OmniPro-Accept software from Scanditronix-Wellhofer. A Medtec-TG51 water tank with Max-4000 electrometer and 0.6 cc PTW ionization chamber and a mini phantom from Standard Imaging was utilized for output measurements for millennium-120 MLC (Varian Medical Systems) and SRS diode detector (Scanditronix-Wellhofer) of 0.6 mm diameter of active area and 0.3 mm of active volume thickness for micro-MLC (BrainLab).

The difference in PDD in the build-up region for millennium MLC was ±1.0% for 6 MV photons. For 10 MV photons the PDD difference was within ±4.0%. The difference in PDD for 23 MV photons ranged from 0% to 40.0%. PDD difference from build-up depth to about 28 cm was within ±1.0%. Difference in PDD crossed ±1.0% at 30 cm depth for 6 MV photons. The difference in PDD in the build-up region for mMLC was ±8.0% for 6 MV photons. For the smallest field size studied with micro-MLC i.e. 0.6 × 0.6 cm2 difference in PDD was more than ±1.0% in the build-up region and beyond a depth of 8.0 cm. The profiles for jaws and MLC agreed within the umbra region. However in the penumbra region small differences in doses were observed. The collimator scatter factor (Sc), phantom scatter factor (Sp) and output factor values for MLC were different that those for jaws.

The differences in beam characteristics could have implication for intensity modulated radiation therapy and stereotactic radiosurgery in terms of dose in the build up region, exit dose, dose to the planning target volume (PTV) and organ at risk (OAR). Impact of these dosimetric differences between jaw and MLC needs to be further studied in terms of dose volume histograms for PTV and OAR and its further impact on tumor control probability (TCP) and normal tissue complication probability (NTCP).

Open access

Sławomir Żak

Treatment of the Processing Wastewaters Containing Heavy Metals with the Method Based on Flotation

The aim of the studies carried out at full technological scale was to indicate optimal systems of the two-stage precipitation and coagulation (PIX 113 - SAX 18, PAX XL1 - SAX 18, ALCAT 102 - lime milk and SAX 18 - PAX 16) in the process of eliminating heavy metals from wastewaters made in the processing plant producing sub-systems for domestic appliances. Precipitated pollutions were thickened by flocculation and separated by hydrogen peroxide enhanced pressure flotation. The experimental installation of maximal flow capacity: 10.0 m3/d consisted of: the storage-equalization tank, the processing pipe reactor, the pressure flotation station, and the reagent preparation and dosing station. Optimal doses of reagents and a flocculent as well as pressure and saturation time were defined for which maximal reductions in the load of heavy metals were achieved. The usefulness of hydrogen peroxide as a means of enhancing flotation was tested. The use of two-stage precipitation permitted the reduction in heavy metals (Cd, Cu, Cr, Ni, Sn, Zn), eg by applying ALCAT 102 - lime milk at the level exceeding 80%.

Open access

Sławomir Żak, Teresa Rauckyte-Żak, Alfredas Laurinavičius and Paweł Siudziński

Abstract

This paper presents the results of the research conducted on the installation designed for physico-chemical pretreatment of technological wastewater in the volume of up to 5.0 m3/day discharged from the production of protective and decorative coating materials used for wooden surfaces. The subject-matter installation constructed on a mobile pallet, consisted of a storage-averaging tank where concentrations were equalised with the use of circulation aeration and mixing. A variant, preliminary pre-oxidation with the use of hydrogen peroxide was conducted in this tank. A substantial installation set for the wastewater treatment plant consisted of two preliminary tube reactors, one cylindrical-conical processing reactor, stations for preparing and dispensing reagents and the sediment dewatering station. Considerable reductions in main chemical indicators of water pollution were obtained in the installation: both total suspended solids (TSS) and ether extract (EE) - more than 98%, chemical oxygen demand (COD) - 46-54%, biochemical oxygen demand (BOD5) - 39-46%, and free formaldehyde (HCHO) - 14-27% due to the use of pre-oxidation and the acid - alkaine double coagulation by applying the ALCAT 105 - SAX 25 system. The use of pre-oxidation with hydrogen peroxide in doses 250.0-450.0 mg/l and then two-stage coagulation resulted in an increase in the reduction of: COD and BOD5 by ca 10-15%, and HCHO by ca 58-66% with reference to the water pretreatment without pre-oxidation. The assessment of sediments formed during the process of pretreatment was made determining the leachable forms of metals (Cu, Ni and Ti) according to methodology of TCLP in compliance with the US EPA Method 1311.

Open access

J. A. Debortoli, A. C. F. Lacerda, T. R. Lisboa and M. L. Martins

Brazilian fish production in 2010 and it has increased to 2.4 % in 2011, responsible for 215 tons more than the anterior year ( Silveira & Silva, 2011 ). In order to obtain maximum production at low costs, frequently the highest quantity of fish per tank as possible is used, and fish frequently cultivated under high densities that culminate in disease outbreaks. Monogeneans are responsible for major diseases outbreaks in aquaculture, causing great mortality in intensive fish farming ( Paperna et al . 1984 ; Thoney & Hargis, 1991 ; Moraes & Martins, 2004 ; Tu et al

Open access

Abdul Razzaq, Zahid Cheema, Khawar Jabran, Mubshar Hussain, Muhammad Farooq and Mohsin Zafar

., Iqbal M., Ahmad R. 2002. Response of wheat varieties and some Rabi weeds to allelopathic effects of sorghum water extract. Int. J. Agri. Biol. 4 (1): 52-55. Cheema Z. A., Khichi A. H., Khaliq A. 2005. Feasibility of reducing herbicide dose in combination with sorgaab for weed control in transplanted fine rice ( Oryza sativa L.). Int. J. Agric. Biol. 7 (6): 892-894. Cheema Z. A., Luqman M., Khaliq A. 1997. Use of allelopathic extracts of sorghum and sunflower herbage for weed control in wheat. J. Anim. Plant Sci. 7

Open access

Izabela M. Bigaj, Renata Brzozowska, Michał Łopata, Grzegorz Wiśniewski, Julita A. Dunalska, Daniel Szymański and Rafał A. Zieliński

, K.E., Lancelot, C., Likens, G.E., 2009, Ecology: controlling eutrophication: nitrogen and phosphorus, Science 323 (5917): 1014-1015. Cooke G.D., Welch E.B., Peterson S.A., Newroth P.R., 1993, Restoration and Management of Lakes and Reservoirs, Lewis Publ., Boca Raton, p. 548. Ducoste J.J., Clark M.M., 1998, The influence of tank size and impeller geometry on turbulent flocculation: I. Experimental, Environ. Eng. Sci. 15(3): 215-224. Francois R.J., 1987, Strength of aluminium hydroxide flocs, Water Res. 21(9): 1023

Open access

B. Wysok, A. Wiszniewska-Łaszczych, J. Uradziński and J. Szteyn

, Hegde NV, Brown JL ( 2006 ) A survey of foodborne pathogens in bulk tank milk and raw milk consumption among farm families in Pennsylvania. J Dairy Sci 89: 2451-2458. Keene WE ( 1999 ) Lessons from investigations of foodborne disease outbreaks. JAMA 281: 1845-1847. Korsak N, Daube G, Ghafir Y, Chahed A, Jolly S, Vindevogel H ( 1998 ) An efficient sampling technique used to detect four foodborne pathogens on pork and beef carcasses in nine Belgian abattoirs. J Food Prot 61: 535-541. Lander KP