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Abstract  

We have developed a thermogravimetric system (TG system) for condensable gas adsorption by modifying a standard thermogravimetric analyzer Cahn TG 2121 and performed isotherm measurements of water vapor adsorption on Fuji Davison type RD silica gel and ethanol vapor adsorption on Maxsorp II activated carbon. For the water vapor-silica gel data, our results compare favorably with the data reported by the manufacturer and those obtained from a volumetric method. This confirms the reliability of our TG system for adsorbents which do not swell significantly. In addition, our isotherm data also provide useful design information for the development of adsorption chillers.

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Thermogravimetric analysis

A tool to evaluate the ability of mixtures in consolidating waterlogged archaeological woods

Journal of Thermal Analysis and Calorimetry
Authors: D. Donato, G. Lazzara, and S. Milioto

Abstract  

Waterlogged archaeological woods (Pinus pinaster, Ulmus cf. minor and Fagus sylvatica L.) were consolidated by using Colophony, Rosin 100, and a mixture of Poly(ethylene) glycol (PEG) 3000 and Poly(propylene) glycol (PPG) 425. The efficiency of the consolidants was estimated by determining the content entrapped into the cavity of degraded wood. For this purpose, thermogravimetry was demonstrated to be a reliable tool. In the case that the polymeric mixture was used for impregnation, it was also possible to discriminate the amount of PEG 3000 from that of PPG 425 captured by the wood capillaries. Regardless of the wood nature, all the consolidants were present in treated samples in large amount (at least 70% w/w). Thermogravimetric results were in agreement with those calculated by using the wood degradation degree and composition of the consolidant mixture. One of the advantages of using this technique consists into requiring very small amounts (a few mg) of sample against the grams necessary for the conventional experiments.

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Thermogravimetric analysis on gasification reactivity of Hailar lignite

Influence of inherent mineral matters and external ash

Journal of Thermal Analysis and Calorimetry
Authors: Ao Hou, Ze Wang, Wenli Song, and Weigang Lin

al. [ 6 ] investigated the influence of mineral matters on the Greek lignite gasification by thermogravimetric analysis (TG) and fixed-bed reactor. They found that Ca, Na, K, and Mg elements have distinct catalytic effects on promoting gasification

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. Thermoanalytical techniques such as thermogravimetric analysis (TG) and derivative thermogravimetry (DTG) are commonly used to investigate the pyrolytic characteristics and kinetics of solid raw materials [ 9 , 10 ]. In TG, the mass loss of a sample is measured

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Abstract  

Dimensionless number has been developed and introduced for quantitative analysis of the effect of thermogravimetric measuring factors like sample quantity, heating rate, etc. The TG, DTG and T data of different thermogravimetric measurements can be used directly for calculation of the three constants of analogy. TG data of CaCO3 measured in very different conditions show the method of transformation and its applicability for calculation of the correlation of measurements.

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and reaction kinetics related to feedstock. Thermoanalytical techniques are the most common tools for studying the thermal characteristics and kinetics of biomass pyrolysis. Thermogravimetric (TG) analysis is one of these techniques in which

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. Thermogravimetry (TG) is the most commonly used technique for thermal analysis. Thermogravimetric analysis (TGA) measures mass or weight loss as a function of time and temperature to determine kinetic parameters which involves both thermal and isothermal techniques

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-isothermal thermogravimetric (TG) technique at different heating rates. From the TG data, the fraction converted ( α ) was determined at each heating rate. Two model-free methods, i.e. Flynn–Wall–Ozawa (FWO) [ 9 , 10 ] and Kissinger–Akahira–Sunose (KAS) [ 11 , 12 ] were used

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been studied using thermal analysis techniques. This paper reports the changes in the structure of a montmorillonitic clay with adsorbed-intercalated organic acids. X-ray diffraction and high-resolution thermogravimetric analyses are used to

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Thermogravimetric investigation of ancient ceramics

Metrological analysis of sampling

Journal of Thermal Analysis and Calorimetry
Authors: V. Drebushchak, Ljudmila Mylnikova, and V. Molodin

Abstract  

Sherds from restored ancient pots taken from archaeological sites of Siberian region (Late Bronze and Early Iron Age, IX–VIII to VII–VI BC) were investigated by thermogravimetry in order to define the effects of sampling. Three types of the sampling were (1) scanning through the inner surface of a pot, (2) outer surface, core, and inner surface of thick-walled sherds, and (3) random fragments of a restored pot. The results of the measurements were shown to depend on two factors, clay paste composition and firing conditions. Redistribution between mass loss at dehydration and dehydroxylation was detected for the ancient ceramics after ‘mild’ firing. The results of the measurements are explained in terms of a temperature profile throughout the wall of a pot during the thermal treatment under firing and cooking meal. The main conclusion of the work is that the thermogravimetric measurements will be very useful for the solution of archaeological problems only if the sampling is correct.

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