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Abstract Photocatalytic hydrogen production as a technology to solve energy and environmental problems exhibits great prospect and the exploration of new photocatalytic materials is crucial. In this research, the ternary composite catalyst of MoS2/Fe2O3/g-C3N4 was successfully prepared by a hydrothermal method, and then a series of characterizations were conducted. The characterization results demonstrated that the composite catalyst had better photocatalytic performance and experiment results had confirmed that the MoS2/Fe2O3/g-C3N4 composite catalyst had a higher hydrogen production rate than the single-component catalyst g-C3N4, which was 7.82 mmol g−1 h−1, about 5 times higher than the catalyst g-C3N4 (1.56 mmol g−1 h−1). The improvement of its photocatalytic activity can be mainly attributed to its enhanced absorption of visible light and the increase of the specific surface area, which provided more reactive sites for the composite catalyst. The successful preparation of composite catalyst provided more channels for carrier migration and reduced the recombination of photogenerated electrons and holes. Meanwhile, the composite catalyst also showed higher stability and repeatability.

To realize the real-time automatic identification of adulterated minced mutton, a convolutional neural network (CNN) image recognition model of adulterated minced mutton was constructed. Images of mutton, duck, pork and chicken meat pieces, as well as prepared mutton adulterated with different proportions of duck, pork and chicken meat samples, were acquired by the laboratory’s self-built image acquisition system. Among all images were 960 images of different animal species and 1200 images of minced mutton adulterated with duck, pork and chicken. Additionally, 300 images of pure mutton and mutton adulterated with duck, pork and chicken were reacquired again for external validation. This study compared and analyzed the modeling effectiveness of six CNN models, AlexNet, GoogLeNet, ResNet-18, DarkNet-19, SqueezeNet and VGG-16, for different livestock and poultry meat pieces and adulterated mutton shape feature recognition. The results show that ResNet-18, GoogLeNet and DarkNet-19 models have the best learning effect and can identify different livestock and poultry meat pieces and adulterated minced mutton images more accurately, and the training accuracy of all three models reached more than 94%, among which the external validation accuracy of the optimal three models for adulterated minced mutton images reached more than 70%. Image learning based on a deep convolutional neural network (DCNN) model can identify different livestock meat pieces and adulterated mutton, providing technical support for the rapid and nondestructive identification of mutton authenticity.

To improve the corneal permeability and water-solubility of disulfiram (DSF), which is an ocular drug for cataract, P188 was selected as a matrix to prepare solid dispersion of DSF (DSFSD) by hot melt method. The DSFSD was characterized by DSC, XRD, and IR, and the results suggested that DSF was amorphous in DSFSD. The DSFSD was added to borate buffer solution (BBS) contained 20% poloxamer P407 and 1.2% poloxamer P188 to form in-situ gel. In vitro and in vivo experiments revealed that DSFSD combined with in-situ gel (DSFSD/in-situ gel) increased the residence time and the amount of DSF penetrated through the corneal. The pharmacodynamics studies exhibited DSFSD/in-situ gel delayed the development of selenium-induced cataract at some content. These results investigated that DSFSD/in-situ gel as a drug delivery system can improve DSF ocular permeability. Keywords: Disulfiram, Solid dispersion, In-situ gel, Permeability, Anti-cataract

The Shenqi Fuzheng injection (SFI) represents a traditional Chinese medicine (TCM) formulation integrating Astragalus membranaceus (Huangqi, HQ) and Codonopsis pilosula (Danshen, DS). This investigation delved into elucidating the potential mechanisms and molecular targets of SFI in the context of chronic obstructive pulmonary disease (COPD) through comprehensive network pharmacology and molecular docking analyses. Initially, we probed the databases for potential bioactive compounds of SFI and identified relevant COPD-related target genes. Subsequent analyses, conducted using Cytoscape 3.9.1 and STRING, facilitated the construction of a protein-protein interaction (PPI) network to discern key target genes. Following this, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were employed to delineate putative SFI-related signaling pathways, and the results were validated through molecular docking analyses. The network pharmacology analyses revealed a total of 65 active components (35 associated with DS and 30 with HQ) and 233 key targets. Notably, the top five bioactive components (quercetin, apigenin, daidzein, kaempferol, and luteolin) and the top five targets (TP53, AKT1, EP300, MAPK1, and JUN) exhibited substantial affinity and stable binding, with a binding energy ≤ -5.0 kcal/mol in molecular docking analyses. These findings suggested that SFI potentially exerted therapeutic effects on COPD through the concerted action of multiple compounds and pathways. Additionally, the outcomes of this study laid a solid foundation for understanding the pharmacological aspects of SFI, offering valuable insights for its prospective clinical application as an adjuvant therapeutic agent for COPD. [ABSTRACT FROM AUTHOR]

Through the use of ambient pressure X-ray photoelectron spectroscopy (APXPS) and a single-sided solid oxide electrochemical cell (SOC), we have studied the mechanism of electrocatalytic splitting of water (H2O + 2e- → H2 + O2-) and electro-oxidation of hydrogen (H2 + O2- → H2O + 2e-) at 700 °C in 0.5 Torr of H2/H2O on ceria (CeO2-x) electrodes. The experiments reveal a transient build-up of surface intermediates (OH- and Ce3+) and show the separation of charge at the gas-solid interface exclusively in the electrochemically active region of the SOC. During water electrolysis on ceria, the increase in surface potentials of the adsorbed OH- and incorporated O2- differ by 0.25 eV in the active regions. For hydrogen electro-oxidation on ceria, the surface concentrations of OH- and O2- shift significantly from their equilibrium values. These data suggest that the same charge transfer step (H2O + Ce3+ ⇔ Ce4+ + OH- + H•) is rate limiting in both the forward (water electrolysis) and reverse (H2 electro-oxidation) reactions. This separation of potentials reflects an induced surface dipole layer on the ceria surface and represents the effective electrochemical double layer at a gas-solid interface. The in situ XPS data and DFT calculations show that the chemical origin of the OH-/O2- potential separation resides in the reduced polarization of the Ce-OH bond due to the increase of Ce3+ on the electrode surface. These results provide a graphical illustration of the electrochemically driven surface charge transfer processes under relevant and nonultrahigh vacuum conditions. [ABSTRACT FROM AUTHOR]

Photoelectron spectroscopic measurements have the potential to provide detailed mechanistic insight by resolving chemical states, electrochemically active regions and local potentials or potential losses in operating solid oxide electrochemical cells (SOCs), such as fuel cells. However, high-vacuum requirements have limited X-ray photoelectron spectroscopy (XPS) analysis of electrochemical cells to ex situ investigations. Using a combination of ambient-pressure XPS and CeO2−x/YSZ/Pt single-chamber cells, we carry out in situ spectroscopy to probe oxidation states of all exposed surfaces in operational SOCs at 750 °C in 1 mbar reactant gases H2 and H2O. Kinetic energy shifts of core-level photoelectron spectra provide a direct measure of the local surface potentials and a basis for calculating local overpotentials across exposed interfaces. The mixed ionic/electronic conducting CeO2−x electrodes undergo Ce3+/Ce4+ oxidation-reduction changes with applied bias. The simultaneous measurements of local surface Ce oxidation states and electric potentials reveal the active ceria regions during H2 electro-oxidation and H2O electrolysis. The active regions extend ∼150 μm from the current collectors and are not limited by the three-phase-boundary interfaces associated with other SOC materials. The persistence of the Ce3+/Ce4+ shifts in the ∼150 μm active region suggests that the surface reaction kinetics and lateral electron transport on the thin ceria electrodes are co-limiting processes. [ABSTRACT FROM AUTHOR]

Fluid Catalytic Cracking (FCC) is a crucial refining process supplying majority of gasoline used worldwide as well as other key building blocks for chemical industry. Nickel, a contaminant in crude oil, deposits on FCC catalysts and induces unwanted dehydrogenation reactions, inhibiting the FCC unit from reaching optimal operation. We describe a new spectroscopic methodology to characterize the impact of boron interaction on nickel in FCC catalysts through a trend analysis of CO DRIFTS for FCC catalysts from boron-based technology. Results obtained by the new method provide direct spectroscopic evidence of boron effect on nickel passivation by decreasing reducibility of nickel.

In this contribution, we present an industrial example on how tailored operando spectroscopic methodologies provide the insights needed for the development of new catalytic technologies and support their global utilization. We describe the use of operando spectroscopic methods to investigate how the CO oxidation performance of catalysts is impacted by NOx, H2, temperature, and moisture, as well as the catalyst support. This operando spectroscopic analysis provides mechanistic insights into the current diesel oxidation catalyst (DOC) system and shines light on the material and process development efforts on future DOC catalysts for low-temperature emission control to meet the new regulations. This investigation has shown that at cold-start temperatures, the nitrate growth can occupy the precious metal–alumina support interfacial sites that are critical for O2 dissociation and/or oxygen transfer and hinder CO conversion. Introduction of hydrogen on the catalyst surface can inhibit the nitrate growth, which in turn keeps these critical interfacial sites open.

Fluid Catalytic Cracking (FCC) has maintained its crucial role in refining decades after its initial introduction owing to the flexibility it has as a process as well as the developments in its key enabler, the FCC catalyst. Boron-based technology (BBT) for passivation of contaminant metals in FCC catalysts represents one such development. In this contribution we describe Fourier Transform Infrared Spectroscopy (FTIR) characterization of boron-containing catalysts to identify the phase and structural information of boron. We demonstrate that FTIR can serve as a sensitive method to differentiate boron trioxide and borate structures with a detection limit at the 1000 ppm level. The FTIR analysis validates that the boron in the FCC catalysts studied are in the form of small borate units and confirms that the final FCC catalyst product contains no detectable isolated boron trioxide phase. Since boron trioxide is regulated in some parts of the world, this novel FTIR methodology can be highly beneficial for further FCC catalyst development and its industrial application at refineries around the world. This new method can also be applied on systems beyond catalysts, since the characterization of boron-containing materials is needed for a wide range of other applications in the fields of glass, ceramics, semiconductors, agriculture, and pharmaceuticals.