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Pavel Vlasák, Zdeněk Chára, Václav Matoušek, Jiří Konfršt and Mikoláš Kesely

-water mixture in inclined pipes. Journal of Hydrology and Hydromechanics, 65, 2, 183–191. VanWijk, J.M., Talmon, A.M., Van Rhee, C., 2016. Stability of vertical hydraulic transport processes for deep ocean mining: an experimental study, Ocean Eng., 125, 203–213. Wilson, K.C., 1976. A unified physically based analysis of solid-liquid pipeline flow. In: Stephens, H.S., Streat, M., Clark, J., Coles, N.G. (Eds.): Proc. HYDROTRANSPORT 4. B.H.R.A., Cranfield, UK, Pap. A1. Wilson, K.C., 1979. Deposition-limit nomograms for particles of various densities in pipeline

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Aqeel Ahmad Taimoor

reported in literature. Mercury and bismuth are usually used because of their superior properties. Recent studies focus on antimony as an active metal to meet mercury and bismuth free environment. Antimony has also shown a wide operational window, favorable negative hydrogen overpotential and low self-stripping [ 17 ]. Both in-situ and ex-situ antimony deposition over the substrate surface has been presented in literature. Although in-situ prepared antimony electrode has superior properties for the detection of Cd and Pb ions [ 18 ] but it adds toxic antimony

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Caroline W. Maina, Joseph K. Sang, Benedict M. Mutua and James M. Raude

., 2014a ; Walling and Quine, 1992 ). Despite these assumptions the use of FRNs provides more information on soil and deposition status in different sites. This method provides an immense potential in data scarce regions. To further improve on the findings the choice of reference sites is critical. Parsons and Foster (2011) reported that use of reference sites in assessing soil erosion and deposition limits the application of FRNs. They argued that samples collected from the same reference sites give high variability of 137 Cs. Another limitation raised by

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Vladimir Mićović, Ana Alebić-Juretić, Nada Matković and Goran Crvelin

rd ed. Boca Raton (FL); CRC Press; 1988. p. 440-3. Greenberg A. Standard Methods for the Examination of Water and Wastewater. 16 th ed. Washington (DC): American Public Health Association; 1985. Uredba o preporučenim i graničnim vrijednostima kakvoće zraka [Regulation on guideline and limit values, in Croatian]. Narodne novine 101/1996. Odluka o proglašenju Zakona o zaštiti zraka [Clean air act, in Croatian]. Narodne novine 48/1995. Zakon o zaštiti zraka [Clean

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Nastase-Dan Ciobota and Gheorghe Gheorghe

identifying and repairing of STL file, Machinery Design & Manufacture (2), 40–42 (2002). [5] Agarwala, M.K. ş.a., Structural quality of parts processed by fused deposition, Rapid Prototyping Journal, Vol. 2, Iss. 4, pp.4 – 19, 1996 [6] Ahn, S., Montero, M., Odell, D., Roundy, S., Wright, P., Anisotropic Material Properties of Fused Deposition Modeling ABS. Rapid Prototyping Journal, Vol. 8, No. 4, pp. 248–257, 2002. [7] Grimm, T., Fused Deposition Modelling: A Technology Evaluation, Time Compression Technologies, Vol. 2, No. 2, pp. 1-6, 2003. [8] Lee

Open access

R. Kowalik

, Electrodepositon of Ag-Se coatings, Archives of Metallurgy and Materials 50 , 1017-26 (2005). [19] R.W. Andrews, D.C. Johnson, Voltammetric deposition and stripping of selenium(IV) at a rotating gold-disk electrode in 0.1 M perchloric acid, Analytical Chemistry 47 , 294-9 (1975). [20] T.E. Lister, B.M. Huang, R.D. Herrick Ii, J.L. Stickney, Elec-trochemical formation of Se atomic layers on Au(100), Journal of Vacuum Science and Technology B: Microelectronics and Nanometer Structures 13 , 1268-73 (1995). [21] T.E. Lister, J.L. Stickney, Formation of the first monolayer

Open access

Aleš Dolný

Abstract

Aeshna caerulea (Azure Hawker) is present as a post-glacial relict in central European mountains. This species is listed as critically endangered in the Czech Republic (very restricted distribution occurring in two isolated populations) and the European population trend of this species is decreasing. The main objective of the study was to estimate the population size of A. caerulea in the Úpa bog National Nature Reserve (Czech Republic) using capture-mark-recapture data. Population estimates of adults using the Schnabel method was 425 (the 95% confidence limits: 248.1 / 992.3), and using the Schumacher-Eschmeyer method was 416 (the 95% confidence limits: 326.8 / 570.4). Imago activity became apparent at the beginning of July. This study has suggested that the possible future threats for the A. caerulea in the Czech Republic are drying up, air nitrogen depositions, eutrophication, pollution of water by external sources, and terrestrification, mainly as a result of global warming.

Open access

Juraj Fazekaš, Danica Fazekašová, Ondrej Hronec, Eva Benková and Martin Boltižiar

Abstract

This paper is focused on the impacts of alkaline and metal deposition on soil and vegetation in the immission field of magnesium factory Jelšava-Lubeník (Slovakia). Soil samples and the foliage of vegetation were obtained from the Jelšava-Lubeník area with specific alkaline pollutants. The examined area is one of the most devastated regions of Slovakia. From the point of view of environmental regionalization, it belongs to an environmentally damaged area of Category 3. The total content of heavy metals in the soil and vegetation (Pb, Zn, Cr, Mn, Mg) were determined by atomic absorption spectrometry and X-ray fluorescence spectrometry. Soil reaction was determined in a solution of 0.01 M CaCl2. Vegetation was assessed by the Braun-Blanquet scale. In conclusion, we can say that spray particles of free magnesium oxide (MgO) strongly influence soil reaction, diversity, and vegetation cover. The research showed that the investigated sites were mostly strongly alkaline; the contents of Cr, Mn and Mg were over the toxicity limit, while the measured values of Pb and Zn did not exceed the limits set by the law. The values that measured significantly above the set limit show contamination that can be considered harmful and toxic. In the monitored species, that is, Agrostis stolonifera, Elytrigia repens and Phragmites australis, an over-limit content of Pb and Zn and toxic contents of Mg and Mn were found.

Open access

Hee-Keun Lee, Kwang-San Chun, Sang-Hyeon Park and Chung-Yun Kang

Abstract

Lately, high production rate welding processes for Al alloys, which are used as LNG FPSO cargo containment system material, have been developed to overcome the limit of installation and high rework rates. In particular, plasma-metal inert gas (MIG) hybrid (PMH) welding can be used to obtain a higher deposition rate and lower porosity, while facilitating a cleaning effect by preheating and post heating the wire and the base metal. However, an asymmetric undercut and a black-colored deposit are created on the surface of PMH weld in Al alloys. For controlling the surface defect formation, the wire feeding speed and nozzle diameter in the PMH weld was investigated through arc phenomena with high-speed imaging and metallurgical analysis.

Open access

Ivan Slávik

Abstract

An impoundment is an engineering construction used for the safe deposition of unexploitable waste from industrial and mining facilities. In terms of the legislative requirements of the Slovak Republic, a “Measurements Project” must be developed for each impoundment. In this document the prerequisites for the safe operation of an impoundment, the limit and critical values of the monitored phenomena and the facts influencing the safety of the impoundment and the area endangered by such a site are also defined. The safety and stability of an impoundment are verified according to a ”Measurements Project” by considering stability at regular time intervals. This contribution presents, in the form of a parametric study, a stability analysis of an ash impoundment. The stability analysis provides an example of the utilization of an information database of the results of the regular monitoring of the geotechnical properties of the materials forming the impoundment´s body and the surrounding rock mass. The stability of the impoundment is expressed for a recent state - without a continuous water level in its body and, at the same time, for a hypothetical limit and critical water level according to the valid “Handling Regulations“.