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Asphalt Mixtures with Limestone Aggregate for Base Layer

Abstract

Asphalt mixtures are mixtures of mineral aggregates, filler, bitumen and eventually additives in proportions determined by recipe designed in the laboratory. Asphalt mixtures used as base course are bituminous concrete.

The natural aggregates are granular materials of mineral origin that come from natural or artificial crushing of the rocks. In our country there are the various rocks: eruptive or magmatic rocks, metamorphic rocks, sedimentary rocks.

To the category of sedimentary rocks belong limestone. Sedimentary rocks are characterized by relatively high porosity and a pronounced stratification, which causes mechanical resistance to be low and vary by direction of load. Due to the structure less dense and weaker mechanical resistance, the limestone are used less in heavy traffic pavement structures.

This paper presents an asphalt mixture recipe for the base layer developed in the Laboratory of Roads from Technical University of Civil Engineering Bucharest (TUCEB), using limestone aggregates extracted from Hoghiz Quarry. The paper contains laboratory test results to determine the recipe and laboratory findings leading to the schedule of product.

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Minority cereals cultivated under loaded model conditions / Rzadkie gatunki zbóż uprawiane w warunkach obciążenia metalami ciężkimi

-1820. MELICHÁČOVÁ S. 2007. Využitie netradičných rastlinných druhov na výrobu funkčných potravín, Nitra, SPU NITRA, dizertačná práca: 81-95. NICHOLSON F., SMITH S., ALLOWAY B., CARLTON-SMITH C., CHAMBERS B. 2003. An inventory of heavy metals inputs to agricultural soils in England and Wales. Science of the Total Environment. 311: 205-219. RAMOS-MIRAS J., ROCA-PEREZ L., GUZMÁN-PALOMINO M., BOLUDA R., GIL C. 2011. Background levels and baseline values of available heavy metals in Mediterranean greenhouse soils (Spain). Journal of Geochemical

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Heavy Metals Baseline Concentrations in Soft Tissues of Patella Sp. From the Stratoni Coastal Environment, Ne Greece / Bazowy Poziom Zanieczyszczeń Metalami Ciężkimi W Tkankach Miękkich Patella Sp. Występujących W Przybrzeżnych Obszarach Stratoni, Grecja

References [1] Rainbow PS. Biomonitoring of heavy metal availability in the marine environment. Mar Pollut Bull. 1995;31:183-102. [2] Phillips DJH. The use of biological indicator organisms to monitor trace element pollution in marine and estuarine environments - A review. Environ Pollut. 1977;13:281-317. [3] Navrot J, Amiel AJ, Kronfeld J. Patella Vulgata: A biological monitor of coastal metal pollution - a preliminary study. Environ Pollut. 1974;7:303-308. [4] Lobel PB, Mogie P, Wright

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Lead in soils and pine tree bark (Pinus sylvestris L.) from park area exposed to automotive contamination / Ołów w glebach i korze sosny (Pinus sylvestris L.) z obszaru parkowego, narażonego na zanieczyszczenia motoryzacyjne

References ADACHI K.,TAINOSHO Y. 2004. Characterization of heavy metal particles embedded in tire dust. Environment International 30, 8: 1009-1017. BARAN A., SPŁAWEK I., JASIEWICZ CZ. 2007. Zawartość metali ciężkich w roślinach i gruntach przylegających do wybranych stacji paliw w Krakowie. Materiały II Konferencji Młodych Uczonych, Kraków : 265-272. CHRZAN A., MARKO-WORŁOWSKA M., ŁACIAK T. 2010. Zanieczyszczenie gleby i kory sosny metalami ciężkimi w Parku Krajobrazowym Skałki Twardowskiego w Krakowie

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Microbiological and physico-chemical composition of sewage sludge derived from the food industry / Skład mikrobiologiczny i fizykochemiczny osadów ściekowych pochodzących z przemysłu spożywczego

Abstract

The aim of the study was to analyze the microbiological and physico-chemical composition of sewage sludge from the food industry. The research material was dewatered sewage sludge with and without lime, derived from the water and drink production plant in the Opole region, obtained for testing in March 2013. Physico-chemical analysis included the determination of: pH, temperature of sludge, sedimentation properties, the dry weight, mineral substances, biogenic elements and heavy metals. Microbiological evaluation included quantitative and qualitative determination of mesophilic, psychrophilic and potentially pathogenic microorganisms. Sewage sludge with and without lime characterized similar physico-chemical parameters. However, the addition of lime to the sludge led to a change in ratios of different groups of microorganisms. In the sludge with lime, we observed reduction in the number of mesophilic bacteria and yeast, and total inhibition of psychrophilic bacteria and fungi. Knowledge of the physico-chemical parameters and microbiological composition of the sewage sludge is needed to determine the directions of their development

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Inorganic nanomaterials in the aquatic environment: behavior, toxicity, and interaction with environmental elements

Abstract

The aim of this paper is to present characteristics, toxicity and environmental behavior of nanoparticles (NPs) (silver, copper, gold, zinc oxide, titanium dioxide, iron oxide) that most frequently occur in consumer products. In addition, NPs are addressed as the new aquatic environmental pollutant of the 21st century. NPs are adsorbed onto particles in the aquatic systems (clay minerals, fulvic and humic acids), or they can adsorb environmental pollutants (heavy metal ions, organic compounds). Nanosilver (nAg) is released from consumer products into the aquatic environment. It can threaten aquatic organisms with high toxicity. Interestingly, copper nanoparticles (Cu-NPs) demonstrate higher toxicity to bacteria and aquatic microorganisms than those of nanosilver nAg. Their small size and reactivity can cause penetration into the tissues and interfere with the metabolic systems of living organisms and bacterial biogeochemical cycles. The behavior of NPs is not fully recognized. Nevertheless, it is known that NPs can agglomerate, bind with ions (chlorides, sulphates, phosphates) or organic compounds. They can also be bound or immobilized by slurry. The NPs behavior depends on process conditions, i.e. pH, ionic strength, temperature and presence of other chemical compounds. It is unknown how NPs behave in the aquatic environment. Therefore, the research on this problem should be carried out under different process conditions. As for the toxicity, it is important to understand where the differences in the research results come from. As NPs have an impact on not only aquatic organisms but also human health and life, it is necessary to recognize their toxic doses and know standards/regulations that determine the permissible concentrations of NPs in the environment.

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Geochemistry of rare earth elements in the Baba Ali magnetite skarn deposit, western Iran – a key to determine conditions of mineralisation

References Amiri, M., 1995. Petrography of the Almouglagh . University of Tarbiat-e-Moalem, Tehran, Iran, 231 pp. (in Persian) Asadi, S., 2009. Study of iron mineralization in metamorphic rock in Kohe germez – Kohe sorkh (Qatruyeh) . University of Shiraz, Shiraz, Iran, 154 pp. (in Persian) Aubert, D. Stille, P. & Probst, A., 2001. REE fractionation during granite weathering and removal by waters and suspended loads: Sr and Nd isotopic evidence. Geochimica et Cosmochimica Acta 65, 387–406. Barud, J., 1975. Geological Map of the

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The Effect of Foliar Nutrition with Nitrogen, Molybdenum, Sucrose and Benzyladenine on the Contents of Dry Weight, Cd, Cu and Zn in Carrot

References Adamec L. 2002. Leaf absorption of mineral nutrients in carnivorous plants stimulates root nutrient uptake. New Phytologist 155: 89-100. Borkowska B. 1997. Cytokininy. pp. 60-71. In: Regulatory wzrostu i rozwoju roślin. Właściwości i działanie (S. Jankiewicz ed.). PWN Warszawa, Poland. [in Polish] Chłopecka A. 1994. Wpływ różnych związków kadmu, miedzi, ołowiu i cynku na formy tych metali w glebie oraz na ich zawartość w roślinach. IUNG Seria R, Puławy. pp 65. [in Polish

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Factors affecting heavy metals accumulation in potato tubers / Czynniki wpływające na akumulację metali ciężkich w bulwach ziemniaka

mushrooms by heavy metals in a former mercury-mining area. Journal of Environmental Science and Health Part B, 49: 815-827. BIELEK P. 1996. Soil protection. Code of Good Agricultural Practice in Slovak Republic. VÚPÚ : Bratislava. [in Slovak] BURLINGAME B., MOUILLÉ B., CHARRONDIÈRE R. 2009. Nutrients, bioactive non-nutrients and anti-nutrients in potatoes. Journal of Food Composition and Analysis, 22: 494-502. CHEN X., WANG K., WANG Z., GAN C., HE P., LIANG Y., JIN T., ZHU G. 2014. Effects of lead and cadmium co-exposure on bone mineral

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Thallium Toxicity in Humans

://www.gezondheidsraad.nl/en/publications/health-based-reassessment-administrative-occupational-exposure-limits-thallium-and-wate Cheam V, Garbai G, Lechner J, Rajkumar J. Local impacts of coal mines and power plants across Canada: I. Thallium in waters and sediments. Water Qual Res J Can 2000;35:581-607. Cheam V. Thallium contamination of water in Canada. Water Qual Res J Can 2001;36:851-77. McConnell JR, Edwards R. Coal burning leaves toxic heavy metal legacy in the Arctic. PNAS 2008;34:12140-4. Lin TS, Nriagu J. Thallium speciation in the Great Lakes. Environ Sci Technol 1999

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