Fabrication of Dandelion-like p-p Type Heterostructure of Ag2O@CoO for Bifunctional Photoelectrocatalytic Performance
LANGMUIR
Authors: Yang, Lijun; Hu, Yandong; Su, Mingming; Zhang, Lei
Abstract
A novel three-dimensional purple dandelion-like hierarchical Ag2O@CoO heterojunction with an appropriate redox potential was constructed by chemical precipitation of Ag2O nanoparticle on flower-like CoO. By feat of this hierarchical structure, the Ag2O@CoO photocathode showed significantly high photoelectroreduction activities toward p-nitrophenol (p-NP) and Cr(VI). The high performance of Ag2O@CoO was mainly attributed to the specific structural characteristics and synergistic effect of each chemical component. This hierarchical structure could effectively increase the specific surface area, provide more exposed active edges, and be beneficial for multiple light reflection/ scattering channels and light utilization efficiency. The introduction of Ag2O optimized the composition and further improved the band structure, resulting in an improved separation of photogenerated electrons and holes. The unique photocathode achieves a removal efficiency of 86% for photoelectrocatalytic p-NP degradation after 120 min and 95% for Cr(VI) after 40 min under visible light irradiation with excellent stability. This research provided a simple way for the synthesis of photoelectrocatalytic material with potential applications in the field of environmental governance with visible light illumination.
Multidrug resistance and prevalence of quinolone resistance genes of Salmonella enterica serotypes 4,[5],12:i:- in China
INTERNATIONAL JOURNAL OF FOOD MICROBIOLOGY
Authors: He, Jingjing; Sun, Fan; Sun, Dewei; Wang, Zhenyu; Jin, Shanshan; Pan, Zhiming; Xu, Zhengzhong; Chen, Xiang; Jiao, Xinan
Abstract
Salmonella 4,[5],12:i:- is a monophasic variant of Salmonella Typhimurium, which is responsible for global foodborne disease outbreaks. Here, 255 S. 4,[5],12:i:- strains isolated from humans (11.0%) or food-borne animals (89.0%) between 2010 and 2018 were examined. Tests of susceptibility to 19 antimicrobial agents using the broth micro dilution method showed that 99.2% (n = 253) of the isolates were resistant to at least one compound. Antibiotic susceptibility analysis demonstrated that 91.8% of the isolates were multidrug-resistant (MDR) strains with predominant resistance to tetracycline (90.6%), followed by resistance to ampicillin (86.3%), streptomycin (63.5%), chloramphenicol (62.7%), and trimethoprim-sulfamethoxazole (55.3%). The 5 major distinct patterns of multi-resistance were identified as R-type AST, R-type ACTSxt, R-type ACSTSxt, R-type ACGSTSxt and R-type ASTSxt. Among the PMQR genes examined in this study, oqxAB and aac (6')-Ib-cr were the most prevalent resistance genes in the multi-resistant isolates. Our findings highlight the prevalence of the resistance of S. 4,[5],12:i:- in some regions of China, and several common types of multidrug resistance phenotypes, to provide valuable information for epidemiological studies, risk management, and public health strategies.