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1.
Barkia H. Belkbir L. Jayaweera S. A. A. 《Journal of Thermal Analysis and Calorimetry》2003,71(1):97-106
Organic matter evolution and kinetics of combustion of Tarfaya and Timahdit oil shales have been examined by thermogravimetry (TG) and by differential thermal analysis (DTA). An agreement is observed between both techniques where it was found that combustion of organic matter occurs in two steps. Kissinger's method applied on experimental results gives an activation energy of the same magnitude for the first step of both oil shales (103 kJ mol–1) whereas the second is 148 kJ mol–1 for Timahdit and 118 kJ mol–1 for Tarfaya.The changes in specific surface area during thermal combustion of Timahdit and Tarfaya oil shales have been studied by thermogravimetric gas sorption balance and correlated with experimental results obtained on TG/DTA in air. For Timahdit oil shale oxidation products, specific surface areas calculated from nitrogen adsorption data shows a slight increase during the temperature domain of 280 to 430°C and after this temperature, they increase sharply. However, data obtained with Tarfaya oil shales shows a significant increase at the temperature of maximum oxidation of the first stage of combustion of organic matter.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
2.
S. C. Mojumdar M. Sain R. C. Prasad L. Sun J. E. S. Venart 《Journal of Thermal Analysis and Calorimetry》2007,90(3):653-662
There are many thermoanalytical techniques but only several of them such as thermogravimetric analysis (TG), high resolution
thermogravimetric analysis (Hi-Res™ TG), derivative thermogravimetry (DTG), differential thermal analysis (DTA), calorimetry,
differential scanning calorimetry (DSC), modulated differential scanning calorimetry (MDSC), evolved gas analysis (EGA), transient
thermal analysis (TTA) and thermal conductivity (k) have selected to be discussed in this paper. Simultaneous thermal analysis (STA) is ideal for investigating issues such
as the glass transition of modified glasses, binder burnout, dehydration of ceramic materials or decomposition behaviour of
inorganic building materials, also with gas analysis. Selected applications of various thermoanalytical techniques from medicine
to construction have also been discussed in this paper. 相似文献
3.
K. Rajeshwar 《Thermochimica Acta》1983,63(1):97-112
Instances where differential scanning calorimetry and thermogravimetry have been applied to the study of coals, oil shales and oil sands are reviewed. Work carried out in this laboratory and model studies culled from the literature are used as examples to illustrate a particular application. The topics covered include characterization, assay, thermal stability determination and simulation of processing conditions. 相似文献
4.
5.
Thermal and crystallization studies of short flax fibre reinforced polypropylene matrix composites: Effect of treatments 总被引:1,自引:0,他引:1
The effect of fibre treatments on thermal stability of flax fibre and crystallization of flax fibre/polypropylene composites was investigated. For thermal stability study, flax fibres have been treated using maleic anhydride, maleic anhydride polypropylene copolymer, vinyltrimethoxy silane and alkalization. In order to compare thermal stability of flax fibres thermogravimetry (TG) analysis has been used. Kinetic parameters have been determined by Kissinger method. Results showed that all treatments improved thermal stability of flax fibres. For crystallinity analysis, three different techniques have been used, differential scanning calorimetry analysis (DSC), pressure–volume–temperature (PVT) measurements for analysis of volume shrinkage and polarized optical microscopy (POM). All techniques results showed that addition of flax fibre increased crystallization rate. Besides, depending on fibre surface treatment and crystallization temperature, flax fibre/PP composites can show transcrystallinity. 相似文献
6.
J. Zhang Y. Y. Liu J. L. Zeng F. Xu L. X. Sun W. S. You Y. Sawada 《Journal of Thermal Analysis and Calorimetry》2008,91(3):861-866
Zinc formate dihydrate has been synthesized and characterized by powder X-ray diffraction, elemental analysis, FTIR spectra
and thermal analysis. The molar heat capacity of the coordination compound was measured by a temperature modulated differential
scanning calorimetry (TMDSC) over the temperature range from 200 to 330 K for the first time. The thermodynamic parameters
such as entropy and enthalpy vs. 298.15 K based on the above molar heat capacity were calculated. The thermal decomposition characteristics of this compound
were investigated by thermogravimetric analysis (TG) and differential scanning calorimetry (DSC). TG curve showed that the
thermal decomposition occurred in two stages. The first step was the dehydration process of the coordination compound, and
the second step corresponded to the decomposition of the anhydrous zinc formate. The apparent activation energy of the dehydration
step of the compound was calculated by the Kissinger method using experimental data of TG analysis. There are three sharply
endothermic peaks in the temperature range from 300 to 650 K in DSC curve. 相似文献
7.
Yi-Bo Li Jin-Zhou Zhao Wan-Fen Pu Hu Jia Huan Peng Dong Zhong Sheng-Kui Wang 《Journal of Thermal Analysis and Calorimetry》2013,113(2):579-587
This research aimed at the investigation of the effect of different metallic additive on the combustion and kinetic behavior of crude oil. For this purpose, the thermal behavior of the oil-only and oil–metallic salts mixtures were studies by the thermogravimetry (TG)/derivative thermogravimetry and differential scanning calorimetry (DSC) on heating rate at 10 °C min?1. The result shows that Dagang crude oil exhibited apparent low temperature oxidation (LTO), fuel deposition, and high temperature oxidation processes. With the addition of metallic salts, the LTO process has been shortened and samples added CuSO4, CrCl3·6H2O, and AlCl3·6H2O achieved a much lower peak temperature than that of oil. Based on the Arrhenius model, metallic additives were proven to have obvious influence on the combustion activation energy. And, by comprehensive analysis of TG/DSC profile and activation energy, ZnSO4 exhibited a positive influence on light crude oil combustion during the high pressure air injection process. 相似文献
8.
J. O. Hill 《Journal of Thermal Analysis and Calorimetry》1994,42(2-3):607-621
The research in thermal analysis and calorimetry, conducted by the author over the period 1964 to 1993, is summarised and concisely reviewed. The major investigations have focussed on thermal analysis studies of coordination compounds, particularly the metal dithiocarbamate complexes. A significant solution calorimetric study of some metal dithiocarbamate complexes has also been undertaken. DSC has been applied to determine the sublimation enthalpies of many metal dithiocarbamate and metal pentane-2,4-dionate complexes and solution calorimetry has been applied to study the thermochemistry of the latter group of complexes. Thermal analysis investigations of several inorganic molten salt systems have been initiated. Thermometric titrimetry has been applied to study metal-macrocyclic ligand systems in aqueous media and particularly those systems of environmental significance. Temperature calibration standards for TMA have been proposed and TMA has been applied to study the mechanical properties of several common inorganic compounds. DTA has been applied to study a wide variety of phenols and has subsequently been applied as an analytical technique to determine the components of solid state phenol mixtures. Thermometric titrimetry has been applied to determine the phenolic content of wines. A comprehensive thermal analysis study of Australian brown coal has been undertaken, involving the DSC determination of coal specific energy, a TG/DTA study of the coal pyrolysis and combustion processes and a TG/DTA and EGA study of the cation catalytic effect on the coal pyrolysis process. Thermal analysis and calorimetric techniques have been extensively publicised and promoted by the publication of specialist reviews, the presentation of symposia review papers and the oral presentation of short courses, particularly in the SE Asian region. This review essentially reveals the diversity of possible application of thermal analysis and calorimetric techniques and the primary significance of thermodynamic data in the fundamental rationalisation of chemical phenomena. 相似文献
9.
Carmen Ramírez M. Rico L. Barral J. Díez S. García-Garabal B. Montero 《Journal of Thermal Analysis and Calorimetry》2007,87(1):69-72
The thermal behaviour of an epoxy resin cured with an amine-POSS was studied using differential scanning calorimetry (DSC) and thermogravimetric (TG) analysis. The kinetic of polymerization reaction and the thermal degradation have been analyzed based on an iso-conversional model. The obtained results showed that the activation energies of both processes depend on the degree of conversion. 相似文献
10.
M. Odlyha Q. Wang G. M. Foster J. de Groot M. Horton L. Bozec 《Journal of Thermal Analysis and Calorimetry》2005,82(3):627-636
Dynamic mechanical thermal analysis (DMTA), differential scanning calorimetry (DSC) and thermogravimetry (TG) have been used
to characterise model tapestries, especially woven for the EC-funded project (MODHT) and to historic tapestries in royal palaces
and museums. Modulus values of woollen threads from model tapestries are reported and the effects of traditional dyeing and
mordanting processes quantified. TG, particularly of black woollen threads showed alterations in thermal stability. Tests
of creep on immersion in water and subsequent heating to 90°C and on exposure to a controlled relative humidity programme
were also used to rank these effects. Modulus values of historic woollen samples were also obtained and DSC studies of model
and historic silk samples are reported together with preliminary atomic force microscopy (AFM) images of silk fibres. 相似文献
11.
M. I. B. Bernardi E. Antonelli A. B. Lourenço C. A. C. Feitosa L. J. Q. Maia A. C. Hernandes 《Journal of Thermal Analysis and Calorimetry》2007,87(3):725-730
The results reported here based on a study
of BaTi1–xZrxO3
(x=0, 0.2 and 1) nanometric powders prepared
by the modified Pechini method. The powder samples annealed from 600 to 1000°C/2
h were characterized by thermogravimetric analysis (TG), differential scanning
calorimetry (DSC), X-ray diffraction (XRD) and scanning electron microscopy
(SEM) techniques. The decomposition reactions of resins were studied using
thermal analysis measurements. The barium titanate zirconate system presented
just one orthorhombic phase. Furthermore, this study produced BaTiO3
powders with a tetragonal structure using shorter heat treatments and less
expensive precursor materials than those required by the traditional methods. 相似文献
12.
In this research, non-isothermal pyrolysis behavior and kinetics of three oil shales were studied by thermal analysis methods.
All the thermal effects were endothermic and no exothermic region was observed in DSC curves. When oil shales are heated in
nitrogen atmosphere in TG/DTG, two different mechanisms causing loss of mass were observed. The region between ambient temperature
and 500 K was distillation. The second mechanism was visbreaking and cracking and it was observed between the region 500 and
800 K. Kinetic parameters of all the samples are determined by Coats and Redfern method and the results are discussed with
regard to their accuracy and the ease of interpretation.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
13.
Application of thermal analysis methods for characterization of polymer/montmorillonite nanocomposites 总被引:2,自引:2,他引:0
Agnieszka Leszczynska Krzysztof Pielichowski 《Journal of Thermal Analysis and Calorimetry》2008,93(3):677-687
Thermal analysis is a useful tool for investigating the properties of polymer/clay nanocomposites and mechanisms of improvement
of thermal properties. This review work presents examples of applications of differential scanning calorimetry (DSC), modulated
temperature differential scanning calorimetry (MT-DSC), dynamic mechanical thermal analysis (DMA), thermal mechanical analysis
(TMA), thermogravimeric analysis (TG) and thermoanalytical methods i.e. TG coupled with Fourier transformation infrared spectroscopy
(TG-FTIR) and mass spectroscopy (TG-MS) in characterization of nanocomposite materials. Complex behavior of different polymeric
matrices upon modification with montmorillonite is briefly discussed. 相似文献
14.
B. Ambrozini P. R. Dametto A. B. Siqueira C. T. Carvalho M. Ionashiro 《Journal of Thermal Analysis and Calorimetry》2009,97(2):761-764
Solid state Ln–L compounds, where Ln stands for light trivalent lanthanides (L–Gd) and L is tartrate, have been synthesized.
Thermogravimetry and differential thermal analysis (TG/DTA), differential scanning calorimetry (DSC), X-ray powder diffractometry,
elemental analysis and complexometry were used to characterize and to study the thermal behaviour of these compounds. The
results led to information about the composition, dehydration and thermal decomposition of the isolated compounds. 相似文献
15.
A. C. M. Silva D. A. Gálico R. B. Guerra A. O. Legendre D. Rinaldo M. S. Galhiane G. Bannach 《Journal of Thermal Analysis and Calorimetry》2014,115(3):2517-2520
Simultaneous thermogravimetry–differential scanning calorimetry (TG–DSC) and coupled thermogravimetry–infrared spectroscopy (TG–FTIR) analyses were used to study the antihypertensive drug atenolol. The TG–DSC curves provided information concerning the thermal stability and decomposition profiles of the compound. From the TG–FTIR coupled techniques, it was possible to identify ammonia and isopropylamine as possible volatile compounds released during the thermal decomposition of the drug. 相似文献
16.
Anne M. Garrido Pedrosa M. J. B. Souza A. O. S. Silva Dulce M. A. Melo A. S. Araujo 《Journal of Thermal Analysis and Calorimetry》2006,84(2):503-509
The study of the incorporation
of rare earth elements as additives in Y zeolites is a very interesting field
of research, mainly by its potential application as additives in catalytic
cracking process. In this work was studied the thermal and structural properties
of cerium, holmium and samarium supported on HZSM-12 zeolite. The obtained
materials were characterized by X-ray diffraction (XRD), infrared spectroscopy
(FTIR), nitrogen adsorption, thermogravimetry (TG/DTG), differential scanning
calorimetry (DSC) and differential thermal analysis (DTA). TG/DSC/DTA analyses
showed that the dehydration temperatures of RE/HZSM-12 zeolites (RE=Ce, Ho, Sm) increase in relation to pure HZSM-12.
The acid properties were investigated by pyridine thermo desorption via TG.
The results showed two events of mass loss attributed to elimination of pyridine
adsorbed on the weak+medium acid sites and on the strong acid sites. 相似文献
17.
This study focuses on the use of slow pyrolysis with controlled temperature increase for the thermal decomposition of pre-dried wastewater sludge. A combination of two significantly different methods was applied to investigate the pyrolysis process. The first of the experimental approaches was based on laboratory apparatus with a vertical batch retort equipped with external electrical heating. Samples of the liquid and gaseous products of the pyrolysis were taken at defined intervals throughout the pyrolysis process and were subsequently analysed. The second method involved the application of thermal analysis to the identical sludge, completed by online analysis of the pyrolysis products generated. This second method included thermogravimetry (TG), differential thermal analysis (DTA), and differential scanning calorimetry (DSC). The results obtained by both methods demonstrate that waste water sludge can be effectively converted into pyrolysis gas and oil with good combustion properties. 相似文献
18.
M. L. A. Gonçalves M. A. G. Teixeira R. C. L. Pereira R. L. P. Mercury J. R. Matos 《Journal of Thermal Analysis and Calorimetry》2001,64(2):697-706
The thermal decomposition of asphaltenes is mainly responsible for the formation of coke in petroleum processing. Phenomena
involved are not clearly understood, because of the difficulties to characterize such heavy components. This paper reports
the application of thermal analysis techniques to study the thermal behavior of asphaltenes from Brazilian oil. The approach
involves kinetic studies of the thermal decomposition of asphaltenes under controlled conditions by thermogravimetry (TG),
characterization of volatile fractions by thermogravimetry and differential thermal analysis coupled with gas chromatography/mass
spectrometry (TG-DTA/GC/MS) and by gas chromatography/mass spectrometry (GC/MS) in the volatile recovered. The coke formed
was also studied after being decomposed into smaller molecules using selective oxidation.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
19.
P. S. Thomas B. H. Stuart N. McGowan J. P. Guerbois M. Berkahn V. Daniel 《Journal of Thermal Analysis and Calorimetry》2011,103(2):507-513
The potential of thermogravimetric analysis (TG) as a tool for the characterisation of ochre paint used in indigenous Australian
bark paintings has been investigated. TG has been combined with differential scanning calorimetry (DSC) and mass spectrometry
(MS) to identify and quantify the main inorganic and organic components present in the paints. The results obtained were supported
by comparison with infrared spectra and XRD data obtained for the same specimens. The potential of thermal methods for the
characterisation ochres has been demonstrated, with subtle differences between small samples being able to be identified. 相似文献