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1.
Radiography (Lond) ; 23(3): e72-e74, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28687305

ABSTRACT

Paget Disease of the bone is a metabolic disorder which leads to a profound alteration of the bone's architecture. It may be asymptomatic and, since its radiological features mimic those of bone metastases, may present a diagnostic dilemma during the evaluation of a cancer patient. We illustrate an uncommon monostotic form of the disease, affecting solely the scapula, diagnosed during the staging of a lung cancer patient.


Subject(s)
Lung Neoplasms/diagnostic imaging , Lung Neoplasms/pathology , Osteitis Deformans/diagnostic imaging , Scapula/diagnostic imaging , Aged , Diagnosis, Differential , Humans , Incidental Findings , Lung Neoplasms/therapy , Male , Neoplasm Staging
2.
J Hazard Mater ; 262: 1187-95, 2013 Nov 15.
Article in English | MEDLINE | ID: mdl-22819958

ABSTRACT

An experimental study to evaluate the potential of using indigenous limestones in a passive system to treat acid mine drainage, at a mining zone of Mexico was carried out. Chemical and mineralogical characteristics of four types of native rocks (KIT1, KIT2, KSS, QZ) showed distinct CaCO3 contents. Synthetic aqueous leachates from an old tailings impoundment had a pH of 2.18, 34 mg/L As, 705 mg/L Fetotal, and 3975 mg/L SO4(2-). To evaluate dissolution behavior of rocks, kinetic batch experiments with an acid Fe-rich solution were performed. Decaying kinetic constants adjusting H(+) concentration to a first order exponential process were: KIT1 (k = 2.89), KIT2 (k = 0.89) and KSS (k = 0.47). Infrared spectrum and XRD of precipitates showed schwertmannite formation. To determine As and heavy metals (Fe, Cd, Zn, Al) removal from the synthetic leachates, batch experiments using KIT1 were developed. Arsenic decreased from 34.00 mg/L to 0.04 mg/L, Fe and Al were totally removed, and concentrations of Zn and Cd decreased 88% and 91% respectively. Analyses by IR and SEM-EDS indicate that co-precipitation with Fe-Hydroxides formed upon leachate interaction with limestone is the main As removal process. Chamosite, identified by XRD may participate in the removal of Al, SiO2 and a fraction of Fe.


Subject(s)
Calcium Carbonate/chemistry , Mining , Water Pollutants, Chemical/analysis , Arsenic/chemistry , Environmental Monitoring , Ferric Compounds/chemistry , Geology , Hydrogen/chemistry , Iron/chemistry , Iron Compounds/chemistry , Kinetics , Metals, Heavy/chemistry , Mexico , Microscopy, Electron, Scanning , Models, Chemical , Spectroscopy, Fourier Transform Infrared , X-Ray Diffraction
3.
J Phys Condens Matter ; 22(49): 496003, 2010 Dec 15.
Article in English | MEDLINE | ID: mdl-21406789

ABSTRACT

Ni-doped SnO2 nanoparticles prepared by a polymer precursor method have been characterized structurally and magnetically. Ni doping (up to 10 mol%) does not significantly affect the crystalline structure of SnO2, but stabilizes smaller particles as the Ni content is increased. A notable solid solution regime up to ∼ 3 mol% of Ni, and a Ni surface enrichment for the higher Ni contents are found. The room temperature ferromagnetism with saturation magnetization (MS) ∼ 1.2 × 10 (- 3) emu g (- 1) and coercive field (HC) ∼ 40 Oe is determined for the undoped sample, which is associated with the exchange coupling of the spins of electrons trapped in oxygen vacancies, mainly located on the surface of the particles. This ferromagnetism is enhanced as the Ni content increases up to ∼ 3 mol%, where the Ni ions are distributed in a solid solution. Above this Ni content, the ferromagnetism rapidly decays and a paramagnetic behavior is observed. This finding is assigned to the increasing segregation of Ni ions (likely formed by interstitials Ni ions and nearby substitutional sites) on the particle surface, which modifies the magnetic behavior by reducing the available oxygen vacancies and/or the free electrons and favoring paramagnetic behavior.

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