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1.
Molecules ; 24(15)2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31362458

RESUMO

As persistent organic pollutants, dichlorodiphenyltrichloroethanes (DDTs) and their metabolites pose considerable risks to human health and the environment. Therefore, monitoring DDTs in the environment is essential. Here, we developed a green, simple, and effective magnetic solid-phase extraction (MSPE) method coupled with gas chromatography tandem triple-quadrupole mass spectrometry to determine the DDT content of environmental water samples. A magnetic ionic liquid (IL) adsorbent was developed based on a modified magnetic multiwalled carbon nanotube/zeolitic imidazolate framework-8 (MM/ZIF-8/IL), synthesized by immobilizing the IL on the surface of MM/ZIF-8. We confirmed successful synthesis of MM/ZIF-8/IL by material characterization, and our results suggested that the MM/ZIF-8/IL had a high Brunauer-Emmett-Teller surface area (159.9 m2 g-1), good thermostability (<800 °C), and a high degree of superparamagnetism (52.9 emu g-1). Several experimental conditions affecting the MSPE efficiency were optimized. Under the best conditions, good detection linearity was achieved (0.5-500 µg L-1) with determination coefficients ranging from 0.9927 to 0.9971. The lower limits of detection (0.0016-0.0072 µg L-1) also had good precision, having an intraday relative standard deviation (RSD) ≤ 6.5% and an interday RSD ≤ 8.9%. Finally, we used the as-developed method to determine DDT levels in environmental water samples.


Assuntos
DDT/química , DDT/isolamento & purificação , Líquidos Iônicos , Magnetismo , Nanotubos de Carbono , Extração em Fase Sólida , Poluentes Químicos da Água , Nanotubos de Carbono/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Zeolitas/química
2.
Exp Ther Med ; 16(5): 4260-4264, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30402163

RESUMO

The aim of the current study was to investigate the atrial septal aneurysm (ASA) incidence rate and describe its morphologic features by dual-source computed tomography (DSCT). A total of 8,626 patients (4,284 men and 4,342 women) who underwent DSCT examinations were enrolled. The presence of ASA was defined as the protrusion of the complete or partial interatrial septum with a maximum vertical distance (MVD) from the atrial septum plane of >10 mm during a cardiac cycle and a diameter of the aneurysm base of >15 mm. The MVD and direction of the protrusion, as well as other abnormalities, were recorded. The ASA patients were classified by both gender and directions of protrusion into four groups, including the right atrium (RA) and left atrium (LA) groups in males and females, respectively. Values across groups were compared using the independent-sample t-test and differences in qualitative variables were assessed with the χ2 test. Of the 8,626 patients, 51 (0.6%) were diagnosed with ASA (mean age, 62±10 years), including 23 (0.5%) males and 28 (0.6%) females. There were no significant differences in the age (t=-1.37, P>0.05) and incidence rate (χ2=0.43, P>0.05) between the male and female groups. However, there were significant differences in the mean ages (t=-2.20, P<0.05) and the gender proportions (χ2=7.39, P<0.05) of patients in the RA and LA groups. In the two male groups, no significant differences were observed in the diameters of the ASA bases and MVD in the RA and LA groups. In the female groups, the differences in the MVD of protrusion in RA and LA groups were non-significant, whereas the diameters of the base of ASA demonstrated significant differences (t=2.27, P<0.05). In conclusion, the ASA incidence rate was 0.6%, and electrocardiography-gated DSCT scan served as an alternative diagnostic technique for the detection of ASA. It is essential for radiologists to recognize this clinical entity and to minimize misdiagnoses and missed diagnoses.

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