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the design with minimum error, nano-sized CB (<40 nm) from Cabot, Co. was used as the carbonaceous sample because of the following reasons: (1) to avoid any catalytic reaction during TG, it is important to select a carbonaceous material that has very

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Co-firing of biomass with coals

Part 1. Thermogravimetric kinetic analysis of combustion of fir (abies bornmulleriana) wood

Journal of Thermal Analysis and Calorimetry
Authors: Ahu Gümrah Dumanli, Sinem Taş, and Yuda Yürüm

increased from 18746 to 19521 kJ/kg due to the removal of the low volatile compounds. As the heat treatment temperature was increased to 300 °C and higher temperatures, parallel to the pyrolytic losses of carbonaceous material from the structure of the wood

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Abstract  

The effect of ammoxidation on thermal stability of carbonaceous materials characterised by degree of coalification other than that of brown coal (Konin mine, Poland) or sub-bituminous coal (Sośnica mine, Poland) was studied by thermogravimetric (TG-DTG) method. Analysis of TG-DTG curves has shown that coal samples ammoxidised at the higher temperature show slightly lower thermal stability. It has been established the importance of the sequence in the processes of carbonisation and ammoxidation. Both the amount of nitrogen introduced on the surface of studied carbonaceous materials and the thermal stability of nitrogen groups were affected.

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Abstract  

Modern technology produces a large variety of organic, metallo-organic and inorganic compounds which might be analysed successfully for their stoichiometry by INAA or IPAA if the error sources are kept under control. The problems of comparator materials, irradiation by linear accelerator, measurement and data evaluation including minor corrections are dealt with. Application to TiCN, Si3N4, SiC and nitrogen determination in different carbonaceous materials is reported.

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A method was developed for the determination of trace and subtrace amounts of uranium in organic substances used during the industrial process of nuclear fuel production. The method is based on decomposing 50 g of the sample by wet ashing with 25 g conc. sulfuric acid. The residue from the ashing process was ignited at 525 °C to remove all carbonaceous materials. The residue was boiled with 10 ml of 11 nitric acid. The resulting solutions was analyzed for uranium concentration using a modification of the arsenazo III method which allows for uranium determination after separating it by TBP extraction from all the interfering elements. The proposed method proved to be sensitive (detection limit: 15 ppb). The relative standard deviation of the method for a sample containing 200 ppb uranium is 5%. The dynamic range of the method is wide, since the method is applicable. for trace and subtrace levels of uranium in organic substances.

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Abstract  

A thermogravimetric method based on dynamic heating and the use of an internal source of SO2 (metal sulfates with a suitable range of decomposition temperatures) was used to compare the SO2-binding abilities of various lime-containing materials. By means of this method, furnace and cyclone ashes formed in the combustion of oil-shale in the Baltic Power Station, their differently activated (grinding, hydrating) forms and some carbonaceous materials were investigated to estimate their suitability for exhaust gas purification in thermal power stations.

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Abstract  

The study of fossil materials is very important in the geological and biological researches. They can involve ancient past, evolution or extinction of species, oil prospecting and the understanding of different areas such as: paleoclimate, paleoecology, paleogeography, in addition of climate, environmental changes and life. Araripe Geopark is located in the south area of the Ceará state in the Northeast of Brazil and it provides a general overview of the Earth’s History. In this study the vertebral column extinct fish, Cladocyclus ferox and its nodule from Santana Formation, Northeast of Brazil, calcite and apatite minerals, and vertebral column of recent fish, Opisthonema oglinum were investigated by means of thermal analysis. TG/DTG and DTA curves showed decomposition processes, suggesting water evolution, calcium carbonate and phosphate decomposition and thermal transitions indicated that fossilization processes of fish, carbonaceous material involved the fossil after its death and the organic substance was replaced by inorganic compounds.

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Abstract  

The thermal behavior of the yttria-stabilized zirconia (YSZ) and nickel oxide (YSZ–NiO) composite mixtures with the addition of graphite, multiwall carbon nanotubes and functionalized multiwall carbon nanotubes was studied. The YSZ–NiO composite is the precursor of the YSZ–Ni anode of solid oxide fuel cells. The anode exhibits a porous structure, which is usually obtained by the addition of carbon containing pore formers. Thermal analysis and X-ray diffraction evidenced that the properties of carbonaceous materials (C) and atmosphere have a strong influence on the thermal evolution of the reactions taking place upon heating the anode precursor. The dependence of both the carbon content and the chemical nature of the ceramic matrix on the thermal behavior of the composite were investigated. The discussed results evidenced important features for optimized processing of the anode.

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Abstract  

A combined thermogravimetry/differential scanning calorimetry device (TG/DSC) was coupled to single photon ionisation mass spectrometry (SPI-MS) for evolved gas analysis (EGA). Single photon ionisation (SPI) was performed with a new type of VUV light source, the so called electron beam pumped rare gas excimer lamp (EBEL). SPI does not fragment molecules upon the ionisation process. Thus the molecular mass signature of the evolving gases from thermal composition of carbonaceous material can be directly on-line recorded. In this work the thermo-analytical data and the SPI-MS information on the released organics is presented and discussed for various samples. Namely biomass (soft and hard wood), fossil fuel (crude oil and coal) as well as a complex polymer (ABS) are investigated. The general potential of hyphenating thermal analysis and soft photo ionisation mass spectrometry (EBEL-SPI-MS) for fundamental and applied research and material analysis is discussed.

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. Nakamura S. Wallis 2010 Extending the applicability of the Raman carbonaceous-material geothermometer using data from contact metamorphic rocks

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