Low quantity of Pt loaded onto CeCoOx nanoboxes: Surface-rich reactive oxygen species for catalytic oxidation of toluene.

An optimized oxygen activity of catalysts can facilitate oxidation of volatile organic compounds. This work shows the first construction of Ce-Co oxide thin-walled nanoboxes. Bulk-phase lattice oxygen is activated by metal-metal interactions. The subsequent uniform dispersion of low loaded Pt nanoparticles further enhances the surface-adsorbed oxygen content, and creates an oxygen-rich reaction interface. Competitive adsorption of water vapor was also inhibited, and complete catalytic oxidation of toluene was achieved at low temperature (T90 =140 °C). A diffuse reflectance infrared Fourier-transform spectroscopy probe was used to investigate the adsorption-catalytic process and the possible synergistic catalytic mechanism (Langmuir-Hinshelwood and Mars-van Krevelen). This work provides a strategy for improving the catalyt Crystal structure ic oxidation performance of nanocatalysts for volatile organic compounds by increasing the catalytic oxygen activity.

Characterization of the Complete Chloroplast Genome of Four Species in Callerya.

BACKGROUND: Callerya reticulata (Bentham) Schot, Callerya dielsiana (Harms) P.K. Loc ex Z. Wei & Pedley, Callerya nitida var. hirsutissima (Z. Wei) X.Y. Zhu, and Callerya nitida (Bentham) R. Geesink, which belongs to the Leguminosae family, are important medicinal plants in China. The genus Callerya includes 26 species, 18 species are distributed in China, and the vine stems of some species are used as traditional medicinal herbs because they have important pharmacological activity. Due to the high similarity of appearance, it is difficult to identify them in the market by appearance alone. Therefore, circulating of Callerya-related materia medica on the market is confusing, sometimes even leading to drug safety problems. It is urgent to develop molecular methods for their identification. OBJECTIVE: To sequence and analyze the complete chloroplast (cp) genomes of C. reticulata, C. dielsiana, C. nitida var. hirsutissima, and C. nitida and to analyze their cp genome differences as a basis for seeking easier DNA barcoding for their identification. METHOD: After using Illumina high-throughput sequencing and nanopore sequencing to obtain the genome data, some bioinformatics software was used to assembly and analyze the molecular structure of cp genomes. RESULTS: The complete cp genomes of the four species were circular molecules, which ranged from 130 435 to 132 546 bp, and GC contents ranged from 33.89% to 34.89%. Each of them includes a large single-copy region, a small single-copy region, and without large inverted repeat regions. CONCLUSIONS: These results suggested that highly variable regions of the four cp genomes would provide useful plastid markers, which could be used as a potential genomic resource to resolve phylogenetic questions and provide a reference for mining specific DNA barcodes of these species. HIGHLIGHTS: Our study provided highly effective molecular markers for subsequent phylogenetic analysis, species identification, and biogeographic analysis of Callerya.

Metal-organic frameworks-derived manganese trioxide with uniformly loaded ultrasmall platinum nanoparticles boosting benzene combustion.

Four morphologies of metal-organic frameworks derived Mn2O3 were prepared by calcination of metal-organic frameworks self-assembled from metal ions and organic ligands and loaded with platinum. The catalyst showed excellent catalytic performance for benzene (T90% = 131 °C). ESR (electron spin resonance) test showed that due to the strong electron metal support interaction between Pt and Mn2O3, there were a large number of oxygen vacancies on the surface of the catalyst as active sites to promote the oxidation of benzene. The presence of a large number of Lewis acid sites on the catalyst surface was confirmed by Py-IP (Pyridine adsorption infrared spectroscopy) test. The intermediates of benzene catalytic oxidation are ethyl acetate, carboxylic acids and aldehydes, which can be verified by in-situ DRIFTS. In summary, the catalysts synthesized in this work provide a novel perspective for combining metal-organic frameworks-derived oxides and precious metals for the catalytic oxidation of volatile organic compounds.

Catalytic oxidation of VOCs over 3D@2D Pd/CoMn2O4 nanosheets supported on hollow Al2O3 microspheres.

Catalytic oxidation is a promising method for removing harmful volatile organic compounds (VOCs). Therefore, exploring high-efficiency catalysts for catalyzing VOCs is of great significance to the realization of an environment-friendly and sustainable society. Here, a series of 3D@2D constructed Al2O3@CoMn2O4 microspheres with a hollow hierarchical structure supporting Pd nanoparticles was successfully synthesized. The introduction of hollow Al2O3 for the in situ vertical growth of 2D CMO spinel materials constructs a well-defined core - shell hollow hierarchical structure, leading to larger specific surface area, more accessible active sites and promoted catalytic activity of support material. Additionally, theoretical calculations also indicate that the addition of Al2O3 as the support material strengthens the adsorption of toluene and oxygen on CoMn2O4, which promotes their activation. The dispersion of Pd further strengthens the low-temperature reducibility along with more active surface oxygen species and lower apparent activation energy. The optimum 1 wt% Pd/h-Al@4CMO catalyst possesses the lowest apparent activation energy for toluene of 77.4 kJ mol-1, showing the relatively best catalytic activity for VOC oxidation, reaching 100% toluene, benzene, and ethyl acetate conversion at 165, 160, and 155 °C, respectively. Meanwhile, the 1 wt% Pd/h-Al@4CMO sample possesses excellent catalytic stability, outstanding selectivity, and good moisture tolerance, which is an effective candidate for eliminating VOCs contaminants.

Low Temperature Combustion of VOCs with Enhanced Catalytic Activity Over MnO2 Nanotubes Loaded with Pt and Ni-Fe Spinel.

MnO2 nanotubes loaded with Pt and Ni-Fe spinel were synthesized using simple hydrothermal and sol-gel techniques. After loading with Ni-Fe spinel, the specific surface area of the material increases 3-fold. This change helped to provide more active sites and facilitated the association between the catalyst and volatile organic compounds (VOCs). X-ray photoelectron spectroscopy determined that the adsorbed oxygen concentrations were all greatly increased after Pt loading, indicating that Pt promoted the adsorption of oxygen and so accelerated the combustion process. The performance of the catalyst after loading with 2 wt % Pt was greatly improved, such that the T90 for benzene decomposition was decreased to 113 °C. In addition, the 2% Pt/2Mn@NFO exhibited excellent low-temperature catalytic activity when reacting with low concentrations of toluene and ethyl acetate. This work therefore demonstrates a viable new approach to the development of Mn-based catalysts for the low temperature catalytic remediation of VOCs.

[Molecular mechanism of Spatholobi Caulis in treatment of lung cancer based on network pharmacology and molecular docking].

In this paper, the molecular mechanism of Spatholobi Caulis in the treatment of non-small cell lung cancer(NSCLC) was studied through network pharmacology and molecular docking analysis. With traditional Chinese medicine(TCM) Spatholobi Caulis as the study object, active ingredients of Spatholobi Caulis and corresponding potential drug targets were obtained from Traditio-nal Chinese Medicine Pharmacology Platform(TCMSP) database; GeneCards database was used to collect cancer-related genes; Cytoscape software was used to build Spatholobi Caulis active ingredient-target-pathway relationship network. DAVID database was used for GO and KEGG enrichment analysis of targets, KEGG signaling pathway was visualized, and compounds were screened out for molecular docking. Finally, in vitro experiments on human lung cancer cells, A549 treated with luteolin and licochalcone A were used to preliminarily verify the core targets and pathways, cell proliferation was detected by CCK-8 method, and expressions of caspase-3 and Bax protein were detected by Western blot. A total of 23 active components and 170 potential drug targets were selected from Spatholobi Caulis, involving 127 pathways in total. Molecular docking results showed that licochalcone A,(Z)-3-(4-hydroxy-3-methoxyphenyl)-N-[2-(4-hydroxy-phenyl) ethyl] acrylamide, consumeclose grain successfully docked with the key target EGFR, and binding energy of the three compounds was less than-5 kcal·mol~(-1). CCK-8 results showed that luteolin, licochalcone A, and Spatholobi Caulis extract had the inhibitory effect on human lung cancer A549 cells. Western blot showed that luteolin, licochalcone A and Spatholobi Caulis extract could induce cell apoptosis by increasing the expressions of pro-apoptotic factors caspase-3 and Bax. In this study, the anti-lung cancer effect of Spatholobi Caulis was studied through network pharmacology and molecular docking, in order to provide ideas for the molecular mechanism of Spatholobi Caulis in the treatment of lung cancer.