Oxygen-deficient AgIO for efficiently photodegrading organic contaminants under natural sunlight.

Defect engineering is regarded as an effective strategy to boost the photo-activity of photocatalysts for organic contaminants removal. In this work, abundant surface oxygen vacancies (Ov) are created on AgIO microsheets (AgIO-O) by a facile and controllable hydrogen chemical reduction approach. The introduction of surface Ov on AgIO broadens the photo-absorption region from ultraviolet to visible light, accelerates the photoinduced charges separation and migration, and also activates the formation of superoxide radicals (•O).

Genome-directed discovery of antiproliferative bafilomycins from a deepsea-derived Streptomyces samsunensis.

Genomic bioinformatics analysis identified a bafilomycin biosynthetic gene cluster (named bfl) in the deepsea-derived S. samsunensis OUCT16-12, from which two new (1 and 2, named bafilomycins R and S) along with four known (3-6) bafilomycins were targetly obtained. The structure of 3 was clearly identified for the first time, thus named bafilomycin T herein.

Elucidation of the Late Steps during Hexacosalactone A Biosynthesis in Streptomyces samsunensis OUCT16-12.

Hexacosalactone A (1) is a polyene macrolide compound featuring a 2-amino-3-hydroxycyclopent-2-enone (CN)-fumaryl moiety. While compound 1 has been proposed to be assembled via a type I modular polyketide synthase (PKS) system, most of the putative biosynthetic steps lack experimental evidence. In this study, we elucidated the post-PKS tailoring steps of compound 1 through gene inactivation and biochemical assays.

Study on the long time aging behavior of MAPbI: from experiment to first-principles simulation.

As the core functional layer of perovskite solar cells, the serious issues of the CHNHPbI film related to the long-term stability and its rapid degradation when exposed to the environment should be investigated deeply. In this study, the variation of phase construction, light absorption ability and fluorescence quenching ability during the long time aging process have been monitored. The results show that the degradation process is composed of the original serious fluorescence quenching and the lag behind phase decomposition.

Increasing electron density by surface plasmon resonance for enhanced photocatalytic CO reduction.

The photocatalytic CO reduction reaction is a multi-electron process, which is greatly affected by the surface electron density. In this work, we synthesize Ag clusters supported on InO plasmonic photocatalysts. The Ag-InO compounds show remarkedly enhanced photocatalytic activity for CO conversion to CO compared to pristine InO.

Controllable Schottky barriers and contact types of BN intercalation layers in graphene/MoSiAs vdW heterostructures applying an external electrical field.

Graphene-based van der Waals (vdW) heterostructures have opened unprecedented opportunities for various device applications due to their rich functionalities and novel physical properties. Motivated by the successful synthesis of a MoSiN monolayer (, 2020, , 670), in this work by means of first-principles calculations we construct and investigate the interfacial electronic properties of the graphene/MoSiAs vdW heterostructure, which is expected to be energetically favorable and stable. Our results show that the graphene/MoSiAs heterostructure forms an n-type Schottky contact with a low barrier of 0.

Designing Multifunctional Donor-Acceptor-Type Molecules to Passivate Surface Defects Efficiently and Enhance Charge Transfer of CsPbIBr Perovskite for High Power Conversion Efficiency.

High-density and multitype surface defects of CsPbIBr perovskite induce charge recombination and accumulation, hindering its device efficiency and stability. However, the surface defect types of CsPbIBr perovskite are still unclear, and conventional organic molecules only passivate one specific defect and cannot achieve good overall passivation. Here, density functional theory is used to explore surface defect types and properties of CsPbIBr with calculating the defect formation energy and electronic structure.

Genome-Guided Discovery of Antifungal Filipins from a Deep-Sea-Derived .

Nine new (-, -, , and ; named filipins VI-XIV) and three known (, , and ) filipin-type polyene macrolides were isolated from the deep-sea-derived OUCT16-23 using a genome-guided strategy coupled with bioassay. Their structures were elucidated based on the extensive MS and NMR spectroscopic analyses together with ECD calculations. In an antifungal assay, compounds , , and - showed different degrees of growth inhibition against with minimum inhibitory concentrations (MICs) of 1.

Optimizing the Electronic Structure of ZnS via Cobalt Surface Doping for Promoted Photocatalytic Hydrogen Production.

Developing highly efficient semiconductor photocatalysts for H evolution is intriguing, but their efficiency is subjected to the following three critical issues: limited light absorption, low carrier separation efficiency, and sluggish H evolution kinetics. Element surface doping is a feasible strategy to synchronously break through the above limitations. In this study, we prepared a series of Co-surface-doped ZnS photocatalysts to systematically investigate the effects of Co surface doping on photocatalytic activity and electronic structure.

The effects of flipped classroom characterized by situational and collaborative learning in a community nursing course: A quasi-experimental design.

Background: Since traditional teaching could not help to develop competences, flipped classroom has caught the sight of researchers. Despite the uptake of flipped classroom in other disciplines, there is a dearth of evidence available about the use in nursing curricula. In addition, there is no consensus on how to best implement a flipped classroom.

Bacillaenes: Decomposition Trigger Point and Biofilm Enhancement in .

Bacillaenes are a class of poly-unsaturated enamines produced by strains that are notoriously unstable toward light, oxygen, and normal temperature. Herein, in an in-depth study of this highly unstable chemotype, the stability and biological function of bacillaenes were investigated. The structure change of the bacillaene scaffold was tracked by time-course H NMR data analysis coupled with the differential analysis of 2D-NMR spectra method, which was demonstrated to be a "domino" effect triggered by 4',5'- ( and ) configuration rearranged to trans ( and ).

An Unusual Type II Polyketide Synthase System Involved in Cinnamoyl Lipid Biosynthesis.

As a unique structural moiety in natural products, cinnamoyl lipids (CLs), are proposed to be assembled by unusual type II polyketide synthases (PKSs). Herein, we demonstrate that the assembly of the CL compounds youssoufenes is accomplished by a PKS system that uniquely harbors three phylogenetically different ketosynthase/chain length factor (KS/CLF) complexes (YsfB/C, YsfD/E, and YsfJ/K). Through in vivo gene inactivation and in vitro reconstitution, as well as an intracellular tagged carrier-protein tracking (ITCT) strategy developed in this study, we successfully elucidated the isomerase-dependent ACP-tethered polyunsaturated chain elongation process.

An Effective Strategy for Identification of Highly Unstable Bacillaenes.

Exploration of unstable compounds is a rarely explored area of natural product research. We describe the integration of genomic and metabolomic analyses with bioassay-guided compound mining to effectively explore unstable bacillaenes. New bacillaene structures (, , and ) were identified from compound mixtures using the DANS-SVI (ifferential nalysis of 2D MR pectrum-ingle spectrum with ariable ntensities) method, which were further verified by the isolation of the pure compounds under strictly controlled conditions.

Strategy for chemotherapeutic delivery using a nanosized porous metal-organic framework with a central composite design.

Background: Enhancing drug delivery is an ongoing endeavor in pharmaceutics, especially when the efficacy of chemotherapy for cancer is concerned. In this study, we prepared and evaluated nanosized HKUST-1 (nanoHKUST-1), nanosized metal-organic drug delivery framework, loaded with 5-fluorouracil (5-FU) for potential use in cancer treatment.

Materials And Methods: NanoHKUST-1 was prepared by reacting copper (II) acetate [Cu(OAc)] and benzene-1,3,5-tricarboxylic acid (HBTC) with benzoic acid (CHCOOH) at room temperature (23.

Differences in rheological and fractal properties of conditioned and raw sewage sludge.

Rheological tests for raw and conditioned activated sludge (AS) or anaerobic digested sludge (ADS) show that power-law relationships can be used to describe the evolution of several theological parameters, i.e., limiting viscosity (eta(infinity)), yield stress (tau(y)), cohesion energy of the sludge network (Ec), and storage modulus (G'), with total suspended solid (TSS) content in raw and conditioned sludge.

Effect of solid contents on the controlled shear stress rheological properties of different types of sludge.

Controlled shear stress (CSS) test was used to study the effect of solid contents on the corresponding rheological parameters for sludge. Three types of sludge with or without conditioning, including activated sludge (AS), anaerobic digested sludge (ADS), and water treatment residuals (WTRs), were collected for the CSS test. Results showed that the yield stress and the cohesion energy of the sludge networks were improved with increased total suspending solid (TSS) contents in most cases.