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Factors governing marble lightness in peripheral alteration haloes around carbonate-hosted Zn-Pb-Ag-(Cu-Au) deposits, Garpenberg, SwedenEriksson, Marcus January 2020 (has links)
A Master thesis about the Garpenberg deposit located in Bergslagen, a lithotectonic domain, with a mining history that might date back as far as 350 BC. Marble- and skarn-hosted sulfide deposits are found in the area, which creates the opportunity to mine both limestone and sulfidic ore in a single mine. Garpenberg is such a location hence this thesis, which aims to quantify the factors governing spectrophotometric lightness in marble at the Dammjön ore body. The work is mainly based on five drill cores which were logged and sampled. A total of twenty-seven samples were characterized using lithogeochemical analysis and thin-section analysis. The amount of Acid Insoluble Residue (AIR), magnetic minerals and the spectrophotometric lightness were determined for the same samples. The calcite marble was divided into seven different varieties; 1) calcite marble breccia, 2) light, 3) grey, 4) green, 5) banded salmon pink, 6) ophicalcite and 7) spotted calcite marble. The dolomite marble is white to grey in color and skarn minerals are common and varies between 5-20 vol.%. Grey and light calcite marble are the varieties with the highest spectrophotometric lightness, and it could be shown that the lightness increases with a decreasing amount of titanium, aluminum and zirconium which are chemical proxies for mineralogical impurities of originally volcaniclastic origin. High-quality calcite marble is a potentially economic by-product at the Garpenberg mine, the lightest samples are nearly as light as the light standard used during analysis (92.45 out of 100%). The lightest marble is also the chemically most pure which means that the calcium oxide (CaO) and total-carbon content are high. Key geological factors detrimental to lightness and purity are the primary composition, which is determined by the admixture of volcaniclastic material in the limestone precursor. Hydrothermal alteration with the addition of silicates, sulfides and oxides forms a halo around the massive sulfide lenses. Dolomite marble, which is more proximal to ore, is richer in manganese and sulfides, and not as light as the calcite marble at Dammsjön.
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Fyzikálně-chemické vlastnosti epitaxních vrstev CeO2/Cu(110) / Physically chemical properties of epitaxial films CeO2/Cu(110)Aulická, Marie January 2012 (has links)
In this work ways of preparation of thin epitaxial cerium oxide film on Cu(110) surface were studied. X-ray photoelectron spectroscopy (XPS), X-ray photoelectron difraction (XPD), low energy electron difraction (LEED), ion scattering spectroscopy (ISS) and scanning tunneling microscopy (STM) were used for the characterization of prepared systems. The island structure of CeO2 was prepared by the method of reactive evaporation in oxygen atmosphere. The influence of temperature on the electronic structure and morphology was studied. At the temperature above 550 ˚C partial reduction to Ce2O3 and reordering of the islands to the CeO2(331) structure was observed. The ceria promoted oxidation of copper surface was approved, since the clean c(6x2) reconstruction of the surface was observed at the oxygen exposure 1,5 order of magnitude lower then on Cu(110) alone. The other model system was prepared by cerium evaporation to the oxygen precovered Cu(110) surface. The mix of (2x1) and c(6x2) surface reconstruction was formed by oxygen exposition at 300 ˚C. Cerium was deposited on this surface, also at 300 ˚C. During the following heating to 500 ˚C the formation of epitaxial film Ce2O3(0001) was observed, accompanied by the formation of large hundreds nm long smooth band structures in the [11̄0] direction.
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Experimentální in situ transformace metalurgických odpadů v půdních systémech / Experimental in situ transformation of smelting wastes in soil systemsJarošíková, Alice January 2018 (has links)
Metallurgical activities are one of the important sources of environmental pollution, especially due to inappropriate treatment of waste materials containing potentially harmful elements. Soils in the vicinity of smelting operations are the main target reservoirs for these emitted contaminants. The aim of this study was to depict reactivity of copper smelter flue dusts and slags in aqueous and soil environments using laboratory and field experiments. Slags exhibited high concentrations of As (up to 0.95 wt.%), Cu (up to 2.4 wt.%), Pb (up to 1.02 wt.%), Sb (up to 0.37 wt.%), and Zn (up to 2.45 wt.%). Copper and other metal(loid)s were predominantly bound in sulphides, especially bornite, digenite, chalcocite, and galena. Flue dusts were mainly composed of As2O3 phase (arsenolite and claudetite), with minor amounts of gypsum, galena, quartz and covellite. The main contaminants in the dust were As (53.3 wt.%), Pb (3.41 wt.%), Sb (1.26 wt.%), Zn (1.41 wt.%), Cu (1.07 wt.%) and Bi (0.80 hm.%). The leaching tests performed in the pH range of 3-12 indicated that the release of metal(loid)s from both types of metallurgical wastes was highly pH-dependent. During the leaching in deionised water, up to 42 mg/kg As was released from slags and up to 52.6 g/kg was leached from the flue dust; the latter highly...
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Evaluating the CU-tree algorithm in an HEVC encoder / En utvärdering av algoritmen CU-tree i en HEVC-kodareGrozman, Vladimir January 2015 (has links)
CU-tree (Coding Unit tree) is an algorithm for adaptive QP (quantization parameter). It runs in the lookahead and decreases the QP of blocks that are heavily referenced by future blocks, taking into account the quality of the prediction and the complexity of the future blocks, approximated by the inter and intra residual. In this study, CU-tree is implemented in c65, an experimental HEVC encoder used internally by Ericsson. The effects of CU-tree are evaluated on the video clips in the HEVC Common test conditions and the performance is compared across c65, x265 and x264. The results are similar across all encoders, with average PSNR (peak signal-to-noise ratio) improvements of 3-10% depending on the fixed QP offsets that are replaced. The runtime is not impaired and improvements to visual quality are expected to be even greater. The algorithm works better at slow speed modes, low bitrates and with source material that is well suited for inter prediction. / CU-tree är en algoritm för adaptiv QP. Den körs under framåtblicken (lookahead) och minskar QP för block som refereras av många framtida block, med hänsyn tagen till prediktionens kvalitet och de framtida blockens komplexitet, approximerat av inter- och intra-skillnaden. I denna studie implementeras CU-tree i c65, en experimentell videokodare som används internt på Ericsson. Effekterna av algoritmen utvärderas på videoklippen i HEVC Common test conditions och prestandan jämförs mellan c65, x265 och x264. Resultaten är liknande i alla videokodare, med genomsnittliga PSNR-förbättringar på 3-10% beroende på vilka fasta QP-offsets som algoritmen ersätter. Körtiden påverkas inte nämnvärt och den subjektiva kvaliteten förbättras troligen ännu mer. Algoritmen fungerar bättre med långsamma hastighetsinställningar, låg bitrate samt videoinnehåll som lämpar sig väl för inter-prediktion.
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Size dependent spinodal decomposition in Cu-Ag nanoparticlesErdélyi, Z., Gajdics, B., Tomán, J. J., Radnóczi, G., Bokányi, E., Misják, F. 18 September 2018 (has links)
No description available.
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Wetting of grain boundaries in ultrafine-grained copper by liquid bismuthKosinova, A., Straumal, B., Rabkin, E. 19 September 2018 (has links)
In the present work, we studied the effect of liquid Bi on the microstructure evolution of ultrafinegrained Cu at elevated temperatures.
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Overexpression of CuZnSOD in Coronary Vascular Cells Attenuates Myocardial Ischemia/Reperfusion InjuryChen, Zhongyi, Oberley, Terry D., Ho, Ye Shih, Chua, Chu C., Siu, Brian, Hamdy, Ronald C., Epstein, Charles J., Chua, Balvin H.L. 14 October 2000 (has links)
Superoxide dismutase scavenges oxygen radicals, which have been implicated in ischemia/reperfusion (I/R) injury in the heart. Our experiments were designed to study the effect of a moderate increase of copper/zinc superoxide dismutase (CuZnSOD) on myocardial I/R injury in TgN(SOD1)3Cje transgenic mice. A species of 0.8 kb human CuZnSOD mRNA was expressed, and a 273% increase in CuZnSOD activity was detected in the hearts of transgenic mice with no changes in the activities of other antioxidant enzymes. Furthermore, immunoblot analysis revealed no changes in the levels of HSP-70 or HSP-25 levels. Immunocytochemical study indicated that there was increased labeling of CuZnSOD in the cytosolic fractions of both endothelial cells and smooth muscle cells, but not in the myocytes of the hearts from transgenic mice. When these hearts were perfused as Langendorff preparations for 45 min after 35 min of global ischemia, the functional recovery of the hearts, expressed as heart rate x LVDP, was 48 ± 3% in the transgenic hearts as compared to 30 ± 5% in the nontransgenic hearts (p < .05). The improved cardiac function was accompanied by a significant reduction in lactate dehydrogenase release from the transgenic hearts. Our results demonstrate that overexpression of CuZnSOD in coronary vascular cells renders the heart more resistant to I/R injury.
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Reduction of Nitrates in Water Using Iron and Copper/Iron Bimetallic Particles Supported on ZeolitesSidhu, Harpreet Singh January 2021 (has links)
No description available.
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Numerical Analysis of Diffusion In Crystalline And Polycrystalline Materials-Application to PhotoVoltaicsParikh, Anuja V. 03 May 2019 (has links)
No description available.
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Optimization of The Absorber/Buffer Interface Region of Cu(In,Ga)Se<sub>2</sub> Photovoltaic Devices: A Numerical Simulation StudyPatikirige, Yasas R A 12 August 2019 (has links)
No description available.
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