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2.
Sci Total Environ ; 870: 161835, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-36731559

RESUMO

With the application of plastic products, phthalates now widely occur in various environmental media. A large number of ecological risk assessment experiments have only been carried out on a single medium such as water or sediment. There are few reports of ecological risk assessments based on the phase states of phthalic acid esters (PAEs) such as the free dissolved state and the dissolved organic carbon (DOC) adsorption state. In this study, the concentrations of the free dissolved state, the DOC adsorption state, and the easily released PAEs in the sediments, as well as the dissolved organic carbon release potential and their influencing factors were calculated in the Dongzhaigang water body. The potential ecological risks posed by state-of-the-art PAEs were investigated. The average concentration of six freely dissolved PAEs in water was 0.542 (0.226-1.115) µg/L, accounting for 76.3 % of the total PAEs. The PAEs with the highest concentrations in the free dissolved state were di-n-butyl phthalate (DBP, 0.383 µg/L), followed by Di(2-ethylhexyl) phthalate (DEHP, 0.094 µg/L). The average concentration of all six PAEs (∑6PAEs) adsorbed by the DOC in the water was 0.172 µg/L, accounting for 23.74 % of all of the PAEs. The DOC-adsorbed DEHP (0.148 µg/L) accounted for about 86 % of the six adsorbed PAEs. Sediment organic carbon may affect the release potential of the DOC through changing the soluble organic carbon concentration. Most types of PAEs in water posed low risk to organisms. However, DBP posed low and medium risk to algae and crustaceans, and medium risk to fish. Medium or high risk of DEHP to algae, crustaceans and fish was observed. The high ecological risk of PAEs related to sediments were only found at S13 and S14. Generally, the potential ecological risk of PAEs in sediment was more stable than that in water bodies.


Assuntos
Dietilexilftalato , Ácidos Ftálicos , Poluentes Químicos da Água , Áreas Alagadas , Matéria Orgânica Dissolvida , Ésteres , Dibutilftalato , Medição de Risco , Água , Carbono , China , Poluentes Químicos da Água/análise
3.
Am J Cardiol ; 187: 1-9, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36459730

RESUMO

Real-time 3-dimensional echocardiography combined with speckle tracking was used in this study. A total of 90 patients with normal left ventricular ejection fraction were divided into 3 groups according to the pacing site: left bundle branch area pacing (LBBAP), right ventricular septal pacing (RVSP) or right ventricular apical pacing (RVAP). Procedure duration (90 ± 18 vs 61 ± 6.6 vs 58 ± 5.6 minutes, p = 0.015), Fluoroscopy duration (15.5 ± 5.4 vs 4.8 ± 2.2 vs 4 ± 1.9 minutes, p = 0.004), and ventricular capture threshold at implantation (0.8 ± 0.3 vs 0.6 ± 0.2 vs 0.6 ± 0.1 V, p = 0.002) were significantly increased in patients that received LBBAP compared with RVSP or RVAP. At 4 weeks of follow-up, brain natriuretic peptide levels were significantly lower (22 [12 to 59] vs 135 [86 to 231] vs 235 [147 to 428] pg/ml, p = 0.04), paced QRS duration was significantly shorter (115 ± 26 vs 134 ± 28 vs 157 ± 29 ms, p = 0.012), and global longitudinal strain (-19.4 ± 2.4 vs -19.3 ± 3.4 vs -17.3 ± 3.5%, p = 0.026) and systolic dyssynchrony index (2.5 ± 0.3 vs 5.9 ± 0.9 vs 7.7 ± 1.2, p = 0.001), longitudinal absolute maximum difference of time to peak strain (17 [6 to 68] vs 117 [71 to 173] vs 126 [79 to 178] ms, p <0.0001), and circumferential absolute maximum difference of time to peak strain (76 [32 to 129] vs 148 [117 to 208] vs 161 [118 to 266] ms, p = 0.005) were significantly lower in patients that received LBBAP compared with RVSP or RVAP. In conclusion, LBBAP can provide a more physiological ventricular activation pattern than RVSP or RVAP and results in good left ventricular electrical and mechanical synchronization.


Assuntos
Ecocardiografia Tridimensional , Marca-Passo Artificial , Humanos , Fascículo Atrioventricular , Estimulação Cardíaca Artificial/métodos , Volume Sistólico , Função Ventricular Esquerda/fisiologia , Eletrocardiografia/métodos
4.
Chemosphere ; 77(8): 1132-6, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19775724

RESUMO

This work proposes a new process of recovering Co from spent Li-ion batteries (LIBs) by a combination of crushing, ultrasonic washing, acid leaching and precipitation, in which ultrasonic washing was used for the first time as an alternative process to improve the recovery efficiency of Co and reduce energy consumption and pollution. Spent LIBs were crushed with a 12 mm aperture screen, and the undersize products were put into an ultrasonic washing container to separate electrode materials from their support substrate. The washed materials were filtered through a 2mm aperture screen to get underflow products, namely recovered electrodes. Ninety two percent of the Co was transferred to the recovered electrodes where Co accounted for 28% of the mass and impurities, including Al, Fe, and Cu, accounted for 2%. The valuable materials left in 2-12 mm products, including Cu, Al, and Fe, were presented as thin sheets, and could be easily separated. The recovered electrodes were leached with 4.0M HCl for 2.0 h, at 80 degrees C, along with concurrent agitation. Ninety seven percent of the Li and 99% of the Co in recovered electrodes could be dissolved. The impurities could be removed at pH 4.5-6.0 with little loss of Co by chemical precipitation. This process is feasible for recycling spent LIBs in scale-up.


Assuntos
Cobalto/química , Cobalto/isolamento & purificação , Fontes de Energia Elétrica , Poluentes Ambientais/química , Poluentes Ambientais/isolamento & purificação , Química Verde/métodos , Lítio , Precipitação Química , Química Verde/economia , Concentração de Íons de Hidrogênio , Ultrassom
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