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Human promyelocytic leukemia cells,. HL-60, were treated with cisplattn [cis-diamminedichloroplatinum (II)] (2 itiM, 1 h). DNA- eisplatin-protein complexes were isolated and exposed to thiourea (1M), NaCN (100 mM), diethyldithio-carbamate (500 mM), or tf-methyl-D- glucamine dithiocarbamate (500 mM) for 12 h. The release of platinum was measured by atomic absorption spectroscopy. Sodium cyanide was the most effective agent, releasing about 90% of the DNA-bound platinum. Thiourea was the least effective agent, while dithiocar- bamates exhibited an intermediate. The ability of the same group of agents to split the proteins off from the protein-cisplatin-DNA complex was also evaluated and similarly dithiocarbamate were also the most effective.
Catalytic activity of platinum supported on SnO₂ in the reaction of CO oxidation by NO was examined. Catalysts were tested in gas mixture containing 1 vol.% of NO and 1 vol.% of CO in helium; activation procedure consisted of treatment of the catalysts with CO at 500°C. Improvement of catalytic activity after activation process was observed. The mechanisms of the oxidation and activation process with application of semiconductor resistive sensors made of Pt/SnO₂ were investigated.
Mierzono stężenie platyny w powietrzu nad ulicami Częstochowy i Katowic w 1996 r. Platynę wyłapywano, przepompowując powietrze przez filtry poliwęglanowe o średnicy porów 0,8 µm i oznaczano metodą spektrometrii absorpcyjno-atomowej. W 50 próbkach stwierdzono średnie stężenie platyny 6,69 (SD 1,14) pg/m3.
An increased worldwide usage of platinum group elements (PGE) has been observed during recent decades. High amounts of PGE are applied in such areas as chemical industry and jewellery production, but the increased demand for these metals primarily depends on the introduction of automobile catalytic converter systems. Catalytic converters have also been considered to be a major source of PGE pollution. The similar Pt:Rh ratio, which is used in these autocatalysts, was found in various environmental samples as well. The present literature review indicates that the concentration of these metals has increased considerably in the last twenty years in different environmental matrices, resulting in ecological and human health risks. Because of the importance of PGE and their trace levels in environmental and biological matrices, sensitive methods are required for reliable determination. Details of the particular steps of analytical procedures for PGE quantification in environmental samples such as road dust, airborne particulate matter, soil, benthic sediments, water, wastewater and biological samples are discussed. Sampling and sample storage and preservation techniques are presented. Moreover, the most frequently used extraction, enrichment, detection and determination procedures for PGE are described.
Our paper reports results of a study on the bioavailability of selected elements from sediments deposited by the tsunami event of 26 December 2004 in south Thailand. In January 2005, 15 samples of the sediments deposited by the tsunami were collected at four different localities. The reference sample was collected in an area not affected by the tsunami. In the acid leachable sediments fraction (the bioavailable fraction) the contents of 27 selected elements (Be, Ga, Bi, Rb, Cs, Sn, Mn, Re, Co, Rh, Ru, Mo, V, Nb, Ta, Zr, Sc, Th, Pt, La, Ce, Nd, Eu, Gd, Tb, Ho, Lu) were determined using ICP-MS. The measurements were repeated after one year to establish a potential effect of the rainy season on the content of these elements in this fraction.
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