Відмінності між версіями «Private Information Regarding SAR1B Made Known»

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(Створена сторінка: Soils are lithosols almost devoid of vegetation and the topographical inclination of the sites is 10��C15��. Two additional sites (7 and 7.5) are locate...)
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Поточна версія на 00:19, 19 липня 2017

Soils are lithosols almost devoid of vegetation and the topographical inclination of the sites is 10��C15��. Two additional sites (7 and 7.5) are located at 7 and 7.5?km distance from the smelter with occasional exposure to the plume. These sites are subject to intense gravitational mass movements (slope >45��). No vegetation is found at these sites. Sites 7 and 7.5 are located within the alteration zone surrounding a large porphyry copper deposit. For each location, 15?kg of topsoil was collected from up to 15?cm depth (sites 2.5, 2 and 0.5); the same sampling depth was applied to the rock gravel and dust at sites 7 and 7.5. Topsoil samples were split and one half analysed for grain BMS-354825 manufacturer size by dry sieving using a Ro Tap orbital shaker SO1 from Bibby Stuart, GB. Rocks much larger than coarsest sieve used were removed prior to sieving. Soil mineralogy was determined by X-ray diffraction (XRD) using Rigaku Dmax-C equipment with a horizontal goniometer and operated with Ni-filtered Cu-radiation. Chemical analyses were carried out on four size fractions and the total soil sample for reference: 833�C495?��m (A; abbreviation used in Fig. 3), 246�C147?��m (B), 74�C38?��m (C), SAR1B Experience shows that size fraction ranges A and B are suitable to preserve any rock or aggregates for automated mineral analysis, C and D are size ranges of flue dust particles based on previous observation of captured dust from the smelter. As, Cu, Mo, Pb and Zn were determined following distilled water and diluted sulphuric acid extraction (20% v/v). Water and acid extractions lasted 6?h, using 5?g of samples in 50?mL of water or acid mixed at 150?rev/min. Elemental readings were performed on a Hitachi equipment, Model Z 8100; hydride generation was used to improve the limit of detection of As. The morphology of soil particles in the 74�C38 and see more JSM 5300 scanning electron microscope (SEM). The flue dust pearls and shards of slag-like composition were identified with a Qemscan? (Quantitative Evaluation of Minerals by Scanning Electron Microscopy) system installed on a Tescan Vega 3.5 SEM and equipped with four Xflash Bruker N2L free detectors measuring 10,000 particles per sample, using a point spacing of 2?��m and an accelerating voltage of 25?KV. For measurement and evaluation the Idiscover and Imeasure 4.2 Beta software version was used. Dust samples were dispersed in an Epofix Resin (Struers) with graphite to ensure grain separation. For transmission electron microscope (TEM) observations, a JEOL 1200EXII equipment with a Noran 611EDS detection system was used. Operating voltage was 120?KV. Sites 2.5�C0.5 follow the same grain size distribution trend (Fig. 1). The increase in fine particles size fractions (74�C38?��m and