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1.
Huan Jing Ke Xue ; 44(7): 3997-4005, 2023 Jul 08.
Artículo en Chino | MEDLINE | ID: mdl-37438298

RESUMEN

Microplastics (MPs), as a new type of pollutant, are widely detected in sewage treatment plants. Currently, research on MPs in traditional sewage treatment systems has mainly been focused on the pollution level and distribution characteristics, with a lack of studying the impact of MPs on the sludge granulation. In order to explore the effect of MPs on the granulation process, a microplastic exposure test was conducted by adding polyethylene terephthalate microplastics (PET-MPs), which are widespread in the environment. The operating performance of the system, extracellular polymeric substance (EPS) composition, and flora enrichment were analyzed on the sludge granulation. The results showed that the exposure of PET-MPs significantly accelerated the sludge granulation process, whereas the increase in EPS content dominated by PN enhanced the sludge surface hydrophobicity; the granulation rate and EPS secretion were proportional to the exposed particle size. Microplastics and EPS secretions synergistically promoted the formation of granular sludge. However, continuous microplastic exposure led to deterioration of the system decontamination performance and inhibited the degradation process of pollutants, with the most negative effect of nitrite nitrogen accumulation under 250 µm PET-MPs exposure, as high as (5.08±0.24) mg·L-1. The high-throughput sequencing revealed that the microbial community diversity fell in the experimental group. The dominant bacteria at the phylum level were Proteobacteria and Bacteroidota on the sludge granulation. Rhodocyclaceae, Sphingomonadaceae, Flavobacteriaceae, and Rhodanobacteraceae promoted flocculation by increasing EPS secretion. The decrease in Comamonadaceae and Chitinophagaceae weakened the ammonia and nitrite oxidation capacity of the system, whereas the decrease in Rhodobacteraceae, Hyphomonadaceae, and Xanthomonadaceae inhibited the removal of nitrate nitrogen.


Asunto(s)
Contaminantes Ambientales , Matriz Extracelular de Sustancias Poliméricas , Microplásticos , Plásticos , Aguas del Alcantarillado , Bacteroidetes , Nitrógeno
2.
Food Chem ; 412: 135554, 2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-36708671

RESUMEN

Tetracycline antibiotics (TCs), one of the important antibiotic groups, have been widely used in human and veterinary medicines. Their residues in foodstuff, soil and sewage have caused serious threats to food safety, ecological environment and human health. Here, we reviewed the potential harms of TCs residues to foodstuff, environment and human beings, discussed the luminescence and aptamer sensors based analytical determination, adsorptive removal, and degradation strategies of TCs residues from a recent 5-year period. The advantages and intrinsic limitations of these strategies have been compared and discussed, the potential challenges and opportunities in TCs residues degradation have also been deliberated and explored.


Asunto(s)
Compuestos Heterocíclicos , Contaminantes del Suelo , Humanos , Luminiscencia , Antibacterianos/química , Contaminantes del Suelo/análisis , Inocuidad de los Alimentos , Tetraciclinas/análisis , Tetraciclina/química
3.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 1): m66-7, 2010 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-21522585

RESUMEN

In the title complex, [Zn(C(3)H(2)O(4))(C(12)H(8)N(2))(2)]·5H(2)O, the Zn(II) cation displays a distorted octa-hedral geometry, being coordinated by four N atoms from two 1,10-phenanthroline ligands and two O atoms from different carboxyl-ate groups of the chelating malonate dianion. In the crystal, the complexes are linked into a three-dimensional supra-molecular network by both O-H⋯O hydrogen-bonding inter-actions between water mol-ecules and the uncoordinated carboxyl-ate O atoms of neighboring mol-ecules, and aromatic π-π stacking inter-actions between neighboring phenanthroline rings with centroid-centroid distances of 3.4654 (17) and 3.697 (2) Å.

4.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 12): m1660, 2009 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-21578671

RESUMEN

In the title centrosymmetric dinuclear complex, [Nd(2)(C(27)H(24)Br(3)N(4)O(3))(2)]·6C(3)H(7)NO, the Nd(III) ion is coordinated in a slightly distorted square-anti-prismatic geometry by four N atoms and four O atoms from two centrosymmetrically-related 1,3-bis-[2-(5-bromo-2-oxidobenzyl-amino)eth-yl]-2-(5-bromo-2-oxidophen-yl)-1,3-imidazolidine ligands. The Nd⋯Nd separation is 4.5012 (12) Å.

5.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 8): m903, 2009 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-21583363

RESUMEN

In the title compound, [Cu(C(16)H(12)Br(2)N(2)O(2))], the Cu(II) atom is coordinated in a slightly distorted square-planar geometry by two O and two N atoms of the tetra-dentate dianionic 4,4'-dibromo-2,2'-[ethane-1,2-diylbis(nitrilo-methyl-idyne)]diphen-olate Schiff base ligand.

6.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 8): m1086, 2008 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-21203064

RESUMEN

The title complex, [Cu(2)(C(7)H(6)NO(2))(2)(C(12)H(8)N(2))(2)(H(2)O)(2)]·2C(7)H(7)NO(2)·2H(2)O, consists of a dinuclear [Cu(2)(C(7)H(6)NO(2))(2)(C(12)H(8)N(2))(2)(H(2)O)(2)](2+) cation, two Cl(-) anions, two 4-amino-benzoic acid mol-ecules and two disordered water mol-ecules (site occupancy factors 0.5). The Cu(II) ion adopts a distorted square-pyramidal geometry formed by two N atoms from the 1,10-phenanthroline ligand and two O atoms of the two 4-amino-benzoic acid ligands and one water O atom. The Cu⋯Cu separation is 3.109 (2) Å. A twofold axis passes through the mid-point of the Cu⋯Cu vector.

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