Authors:M. Sánchez, A. Morán, A. Escapa, L. Calvo, and O. Martínez
A thermogravimetric (TG) and mass spectrometric (MS) study was carried out of the process of devolatilization of the organic
fraction of municipal solid wastes (OFMSW) and polyethylene terephthalate (PET). This involved an analysis of the heating
profiles in an inert atmosphere for each of these residues separately and for a mixture made up of half of each by mass. The
fit between the experimental and calculated values was checked by means of the least squares method. No interaction at all
was observed between the two types of waste when the fit between the experimental and theoretical figures was checked, in
the light of the low values obtained from the objective function showing fit. The study of mass spectrometry shows major emissions
of energy-producing gases although fewer pollutants are emitted.
Authors:M. Otero, M. Sánchez, A. García, and A. Morán
To combust coal together with a small percentage
(<10%) of sewage sludge may be an option for the management of these wastes.
Combustion of two different sewage sludge, one semianthracite coal and several
sludges-coal blends (containing different dried mass% of each of the two sewage
sludges) were studied by simultaneous TG/MS dynamic runs carried out at 5C
min–1 in the temperature range 100–800C.
No interactions have been observed between coal and sludge during the blends
combustion. Neither the combustion process, neither the studied emissions
have changed appreciably for the mass% of sludge in the blends considered
in this work.
Authors:L. Calvo, M. Sánchez, A. Morán, and A. García
Sewage sludge disposal is a difficult task owing to increasingly restrictive re-use policies. Its final destination will obviously
depend on its nature and composition but the generation of energy is a significant option. The thermochemical conversion requires
exhaustive gas emission controls. In this regard, this paper offers the results of the use of mass spectrometry together with
a thermogravimetric analysis system used to study the thermal conversion processes of two kinds of sewage sludge under different
atmospheres simulating pyrolysis, gasification and combustion. This TG-MS combination indicates that gasification is the best
process for one kind of sludge while a co-combustion process is more suitable for the other.
Authors:Marta Otero, X. Gómez, A. García, and A. Morán
The combustion of two different sewage sludges and a semianthracite coal was studied and compared by thermogravimetric analysis.
Non-isothermal thermogravimetric data were used to evaluate the Arrhenius parameters (activation energy and the pre-exponential
factor) of the combustion of these carbonaceous materials. The paper reports on the application of model-free isoconversional
methods for evaluating and comparing the corresponding activation energy of the combustion process.
Authors:Lubaina Presswala, M. Matthews, I. Atkinson, O. Najjar, Nadine Gerhardstein, J. Moran, R. Wei, and A. Riga
The thermal analytical study of most hydrophobic and hydrophilic D/L amino acids reveals significant hydropathy index correlation between the presence of water and crystalline amino acids. The
TG derivative mass profiles for arginine and lysine (hydrophilic acids) at various time intervals of atmospheric exposure,
show two distinct peaks, one between 50 and 60°C (unbound water), and one close to 100°C (bound-like water). The DSC heat-cool
profiles for lysine and arginine confirmed the presence of these multiple waters with two heats of vaporization. The absence
of these patterns from the TG and DSC for cysteine and phenylalanine (hydrophobic acids) further supports the conclusions.
Authors:S. Flores-Martínez, J. Martínez, M. Machorro-Lazo, A. García-Zapién, L. Salgado-Goytia, E. Cruz-Quevedo, M. Morán-Moguel, and J. Sánchez-Corona
The analysis of polymorphic markers within or closely linked to the cystic fibrosis transmembrane regulator (CFTR) gene is useful as a molecular tool for carrier detection of known and unknown mutations. To establish the association between mutations in the CFTR gene in western Mexican cystic fibrosis (CF) patients, the distribution of XV2c/KM19 haplotypes was analyzed by PCR and restriction enzyme digestion in 384 chromosomes from 74 CF patients, their unaffected parents, and normal subjects.The haplotype analysis revealed that haplotype B was present in 71.9% of CF chromosomes compared to 0% of non-CF chromosomes. The F508del and G542X mutations were strongly associated with haplotype B (96.7% and 100% of chromosomes, respectively). The haplotype distribution of the CF chromosomes carrying other CFTR mutations had a more heterogeneous background.Our results show that haplotype B is associated with CFTR mutations. Therefore, haplotype analysis is a suitable alternate strategy for screening CF patients with a heterogeneous clinical picture from populations with a high molecular heterogeneity where carrier detection programs are not available. In addition, it may be a helpful diagnostic tool for genetic counseling and carrier detection in the relatives of CF patients and in couples who are planning to have children.