Anomalous fading in TL, OSL and TA – OSL signals of Durango apatite for various grain size fractions; from micro to nano scale

2018 ◽  
Vol 195 ◽  
pp. 216-224 ◽  
Author(s):  
G.S. Polymeris ◽  
I.K. Sfampa ◽  
M. Niora ◽  
E.C. Stefanaki ◽  
L. Malletzidou ◽  
...  
Keyword(s):  
Grain Size ◽  
Size Fractions ◽  
Nano Scale ◽  
Grain Size Fractions

Ti distribution in grain-size fractions of Apollo soils 10084 and 71501

Icarus ◽  
2013 ◽  
Vol 226 (1) ◽  
pp. 891-897 ◽  
Author(s):  
W.G. Kong ◽  
B.L. Jolliff ◽  
Alian Wang
Keyword(s):  
Grain Size ◽  
Size Fractions ◽  
Grain Size Fractions

scholarly journals SEDIMENTÁRNĚ-GEOLOGICKÉ STUDIUM VYBRANÝCH KVARTÉRNÍCH SEDIMENTŮ V OKOLÍ BRNĚNSKÉ PŘEHRADY

2012 ◽  
Vol 19 (1-2) ◽  
Author(s):  
Marek Mikulík ◽  
Slavomír Nehyba ◽  
František Hubatka
Keyword(s):  
Grain Size ◽  
Left Bank ◽  
Quaternary Deposits ◽  
Size Fractions ◽  
Fluvial Deposits ◽  
Arid Conditions ◽  
Loess Deposits ◽  
Surrounding Landscape ◽  
Grain Size Fractions

Outcrops of Quaternary deposits are lining banks of the Brno dam. One of them is situated on the left bank ~ 250 m NW of the Osada pier. The sedimentary profile of Pleistocene deposits is composed of fluvial deposits of the Paleo – Svratka River covered by colluvial and eolian (loess) deposits. Alternation of various facies and various grain-size fractions reveals alternation of more or less arid conditions and also evolution of the surrounding landscape.

Magnetic properties of loess grain size fractions from the section at Paks (Hungary)

1999 ◽  
Vol 116 (1-4) ◽  
pp. 53-64 ◽  
Author(s):  
M Sartori ◽  
F Heller ◽  
T Forster ◽  
M Borkovec ◽  
J Hammann ◽  
...  
Keyword(s):  
Grain Size ◽  
Magnetic Properties ◽  
Size Fractions ◽  
Grain Size Fractions

scholarly journals Mercury in grain size fractions of aggregates and extractive waste from hard coal mining

2017 ◽  
Vol 33 (4) ◽  
pp. 107-123
Author(s):  
Beata Klojzy-Karczmarczyk
Keyword(s):  
Grain Size ◽  
Coal Mining ◽  
Total Mercury ◽  
Mercury Content ◽  
Waste Material ◽  
Hard Coal ◽  
Size Fractions ◽  
Coal Sludge ◽  
Hard Coal Mining ◽  
Grain Size Fractions

Abstract Hard coal production is closely linked to the generation of significant quantities of extractive waste that require further use, in practice recognized as waste or as a raw material. It is therefore important to seek further or improve existing methods of waste material management. Studies conducted in earlier works have shown that it is possible to obtain a low-sulfur grain size fraction (grain class) so that it can be used in excavations requiring reclamation by filling. The purpose of the research presented in this paper is to determine the mercury content in hard coal mining by-products. The presence of mercury in the waste material is known and documented in the literature. However, the level of the content of this element in aggregates or wastes is important. This paper presents the problem of determining the minimum size of rock fractions meeting the specified limits for mercury content above which the material can be considered as safe are used to fill post-mining excavations. The total mercury content was determined using the classical atomic absorption method for all the collected and isolated samples (Altec AMA-254 analyzer). The total mercury content of the samples in the analytical state (Hga) was determined. Laboratory research included waste material directly from production (mining and processing of rock) from the one of the hard coal mine USCB. Coal sludge (silt) (after dewatering on filter presses) and 13 aggregates samples were analyzed, and then separated into 15 grain size fractions. The mercury determination method used in the study allowed its content in the range of 0.0568 to 0.0787 mg/kg, on an average mean of 0.0649 mg/kg (average moisture of the samples - 4.3%). On the other hand, the total mercury content of all the fractions extracted from 13 samples of aggregates showed a high variability in the content of this element, with a noticeabletendency of decreasing mercury content along with the increase in grain size. The average values of the total mercury content decrease from 0.4030 mg/kg for the finest fraction (0-6 mm) to 0.0291 mg/kg for the thickest fraction (120-200 mm) (aggregate sample moisture at approximately 1%). In general, it can be stated that the analyzed samples of coal sludge and grain fractions of aggregates meet the criteria for inert mining waste with respect to the mercury content. Based on the studies conducted, it can be concluded that due to the presence of mercury there is no need to discard fine fractions from aggregates. However, the removal of waste rock material less than 8 mm significantly increases the quality of the material. The obtained results and the statistical analysis clearly indicate a strong correlation between the occurrence of mercury and total sulfur in the material (R2 linear coefficient of determination at 0.9151), where no weathering has yet occurred. In the case of weathering, however, there is no correlation between the occurrence of mercury and sulfur, which may be due to the differences in the processes that govern the transformation and migration of mercury and sulfur compounds.

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