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1.
J Belg Soc Radiol ; 107(1): 84, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37928055

RESUMO

Teaching Point: In rare cases, trauma may result in intramedullary fat globules which have a characteristic aspect both on MRI and dual-energy CT.

2.
Environ Sci Pollut Res Int ; 29(51): 76907-76918, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35670941

RESUMO

Petroleum spent catalysts may contain a significant amount of palladium (Pd) together with other major [aluminum (Al), nickel (Ni), and molybdenum (Mo)] and minor [iron (Fe), lead (Pb), and vanadium (V)] elements. Due to the high intrinsic value of Pd and its scarcity in natural ores, its recovery is highly desired. For this purpose, the ability of a strong basic anionic- resin, Purogold™ A194 resin, to remove Pd from the solution was assessed. Data from kinetic and equilibrium studies, performed under batch mode in 1 mol/L of NaCl and 1 mol/L of HNO3 at (21 ± 1) °C, revealed that the removal of Pd fits well a pseudo-second-order kinetic model [constant rate value, k2, of (0.062 ± 0.010) g/(mmol.min)] and a Langmuir isotherm [maximum sorption capacity of (0.80 ± 0.02) mmol/g with an affinity of resin binding sites towards Pd, KL, of (0.18 ± 0.02) L/mmol], respectively. The sorption of other metals (Al, Fe, Pb, Mo, Ni, and V) that may be present in spent catalyst leachates was tested under similar experimental conditions [CM = 2.5 mmol/L, 1 mol/L of NaCl and 1 mol/L of HNO3 at (21 ± 1) °C)] and the resin showed little affinity towards each one of these metals. Also, simultaneous multi-element batch experiments with Pd and the major components (M = Al, Ni, and Mo ions) ([M]/[Pd] molar ratios between 3.4 and 52 were used) pointed out that the resin is highly selective towards Pd suggesting that the resin can be used in the selective recovery of Pd from petroleum spent catalyst leachates.


Assuntos
Paládio , Petróleo , Troca Iônica , Cinética , Níquel , Vanádio , Adsorção , Alumínio , Molibdênio , Cloreto de Sódio , Chumbo , Íons , Ânions , Ferro , Concentração de Íons de Hidrogênio
3.
Pediatr Radiol ; 50(12): 1691-1708, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32734341

RESUMO

The use of MRI in forensic age estimation has been explored extensively during the last decade. The authors of this paper synthesized the available MRI data for forensic age estimation in living children and young adults to provide a comprehensive overview that can guide age estimation practice and future research. To do so, the authors searched MEDLINE, Embase and Web of Science, along with cited and citing articles and study registers. Two authors independently selected articles, conducted data extraction, and assessed risk of bias. They considered study populations including living subjects up to 30 years old. Fifty-five studies were included in qualitative analysis and 33 in quantitative analysis. Most studies had biases including use of relatively small European (Caucasian) populations, varying MR approaches and varying staging techniques. Therefore, it was not appropriate to pool the age distribution data. The authors found that reproducibility of staging was remarkably lower in clavicles than in any other anatomical structure. Age estimation performance was in line with the gold standard, radiography, with mean absolute errors ranging from 0.85 years to 2.0 years. The proportion of correctly classified minors ranged from 65% to 91%. Multifactorial age estimation performed better than that based on a single anatomical site. The authors found that more multifactorial age estimation studies are necessary, together with studies testing whether the MRI data can safely be pooled. The current review results can guide future studies, help medical professionals to decide on the preferred approach for specific cases, and help judicial professionals to interpret the evidential value of age estimation results.


Assuntos
Determinação da Idade pelo Esqueleto/métodos , Medicina Legal/métodos , Imageamento por Ressonância Magnética/métodos , Adolescente , Osso e Ossos/diagnóstico por imagem , Criança , Humanos , Adulto Jovem
4.
J Radioanal Nucl Chem ; 311(1): 877-886, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28111490

RESUMO

Characterization of cellulose acetate butyrate (CAB) thin films with 17, 35 and 52 wt% butyryl is carried out to select the most suitable matrix material for the U and Pu containing large-sized dried spike reference material. The virgin CAB samples were aged by vibrations, heat, humidity, UV light and X-rays. Characterization was done by thermo-analytical techniques, gel permeation chromatography, mechanical tests and via Rayleigh and Compton scattering. The results show that CAB with lower butyryl content can withstand higher operational temperatures and has greater mechanical strength while CAB with higher butyryl content seems to be more resistant to radiation.

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