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An AgBiS2/BiOI composites with different proportions were prepared by precipitation method, and their catalytic activity was studied by degrading RhB (100 mg/L) under simulated light conditions. The results showed that the photocatalytic activity of AgBiS2/BiOI composite was the best when the doping amount of AgBiS2 was 4 wt. % (the degradation rate was about 94%). Compared with pure BiOI, the degradation rate of RhB increased by 24%. After 5 cycles of experiments, the degradation rate of the material can still reach 94%, indicating that the AgBiS2/BiOI composite has good stability. [ABSTRACT FROM AUTHOR]

Abstract In order to establish a set of perfect heterojunction designs and characterization schemes, step‐scheme (S‐scheme) BiOBr@Bi2S3 nanoheterojunctions that enable the charge separation and expand the scope of catalytic reactions, aiming to promote the development and improvement of heterojunction engineering is developed. In this kind of heterojunction system, the Fermi levels mediate the formation of the internal electric field at the interface and guide the recombination of the weak redox carriers, while the strong redox carriers are retained. Thus, these high‐energy electrons and holes are able to catalyze a variety of substrates in the tumor microenvironment, such as the reduction of oxygen and carbon dioxide to superoxide radicals and carbon monoxide (CO), and the oxidation of H2O to hydroxyl radicals, thus achieving sonodynamic therapy and CO combined therapy. Mechanistically, the generated reactive oxygen species and CO damage DNA and inhibit cancer cell energy levels, respectively, to synergistically induce tumor cell apoptosis. This study provides new insights into the realization of high efficiency and low toxicity in catalytic therapy from a unique perspective of materials design. It is anticipated that this catalytic therapeutic method will garner significant interest in the sonocatalytic nanomedicine field.

The hydroxyl groups generated by hydrolysis are grafted onto the surface of BiPO4, and a stable surface hydroxylation structure is formed during the subsequent calcination process. This would facilitate the formation of a new hydroxyl functional structure on the surface of the parent photocatalyst without damaging its intrinsic structure. Synchronous illumination X‐Ray photoelectron spectroscopy shows that the hydroxyl functional ultrafine BiPO4 can realize the conversion of defective oxygen to lattice oxygen, which is more conducive in improving the photocatalytic efficiency. The process of filling hydroxyl oxygen vacancies and forming a stable structure is explored using in‐ situ infrared spectroscopy. The induced dipole moment promotes the separation of photogenerated electron–hole pairs, which is beneficial for the enhancement of photocatalytic activity. The dipole moment of the hydroxyl functional‐modified ultrafine BiPO4 is −1.409 D compared to −1.385 D for ordinary BiPO4. The results of this study indicate that hydroxyl functional structure and reduced sample granularity are effective strategies to improve the photocatalytic performance of BiPO4.

Based on the self-developed high permeability water pressure loading system, the physical and mechanical properties and pore structure evolution under various high permeability water pressures were studied. This study aims to reveal the microscopic damage mechanism of concrete when subjected to high permeability water pressures. The results indicate that the internal water content increases with the rising of water pressure under various high permeability conditions. Furthermore, the higher the water pressure, the greater the reduction in strength, particularly evident in low-strength-grade concrete. High permeability water pressure causes to the expansion of gelatinized pores with small sizes into transition pores. Moreover, there is a concurrent alteration in both pore size and pore number under high permeability water pressure.

At present, intelligent coal caving in high gas fully mechanized top coal caving face is facing many problems, mainly including poor recognition accuracy of coal gangue, incomplete control research on coal flow and gas concentration, cumbersome design and development of follow-up process, and slow response of control system.In order to solve these problems, this paper developed a cloud side collaborative intelligent coal caving control system based on 5G communication.The system includes 5G network, cloud server, edge processor, terminal execution equipment, etc.It has a high data transmission speed, control response speed and data processing capability.Based on the analysis of fully mechanized coal caving process parameters and intelligent coal caving process flow, elaborates the four key technologies of intelligent coal caving the coal gangue identification technology, big block coal identification and coal flow load balance technology, gas safety linkage control technology, and digital twin technology of coal caving following machine.The application test was carried out in Baode 81309 fully mechanized top coal caving face.After the intelligent fully mechanized top coal caving technology was adopted, the top coal recovery rate increased from 86% to 93%, the coal gangue rate decreased from 21% to 15%, the total production efficiency increased by 10%, and the number of coal caving operators decreased from 3 to 4 to 1 to 2.The cloud edge collaborative intelligent coal caving control system based on 5G communication developed in this paper and its key technologies can also be extended to other fully mechanized coal caving faces, which is of great value for reducing personnel and increasing efficiency and safe and efficient mining of coal mines.

ObjectiveTo understand the presence of virulence genes， molecular typing characteristics， and antibiotic sensitivity of enteroaggregative Escherichia coli （EAEC） in children with diarrhea in Shanghai， so as to provide a scientific basis for EAEC monitoring and standardized treatment of EAEC infection.MethodsEAEC strains isolated from children （≤5 years old） with diarrhea in six districts of Shanghai were collected as the study subjects. EAEC virulence genes were detected by real-time fluorescence quantitative PCR， molecular typing was performed by pulsed-field gel electrophoresis （PFGE）， and drug susceptibility tests were conducted using the microbroth dilution method. χ2 test and two independent samples t-test were used to compare the differences in virulence genes and antibiotic resistance between suburban and urban EAEC strains.ResultsFrom 2019 to 2021， the overall detection rates of gene aggR， pic and astA of 59 EAEC were 30.5%， 50.8%， and 57.6%， respectively. There was no significant difference in the detection rates of virulence genes between suburban and urban EAEC strains （P>0.05）. PFGE analysis revealed that only two EAEC strains belonged to the same PFGE pattern and were collected from the same hospital， and the overall PFGE patterns were polymorphic. EAEC showed susceptibility to imipenem and colistin E， and the resistance rates to sulfamethoxazole （SXT）， ampicillin （AMP）， nalidixic acid （NAL）， and tetracycline （93.1%， 79.3%， 63.8%， and 58.6%， respectively） were higher than 50.0%. The antibiotic resistance rates of cefazolin （CFZ）， cefotaxime （CTX）， and ciprofloxacin （CIP） were significantly different between EAEC strains from suburban and urban areas （P0.05）.ConclusionThe EAEC virulence gene assemblages in children with diarrhea in the six districts of Shanghai are diverse， and the molecular typing patterns are relatively scattered， indicating possible cross-infection of homologous strains. Multi-drug resistance in EAEC strains is relatively common， and there is a statistically significant difference in the resistance rates of CFZ， CTX and CIP between urban and suburban EAEC strains. Attention should be given to standardizing the use of clinical antibiotics to effectively control the dissemination of multidrug-resistant EAEC strains.