Ultralow-Energy-Barrier H_(2)O_(2)Dissociation on Coordinatively Unsaturated Metal Centers in Binary Ce-Fe Prussian Blue Analogue for Efficient and Stable Photo-Fenton Catalysis

The low intrinsic activity of Fenton catalytic site and high demand for light-energy input inhibit the organic-pollution control efficiency of photo-Fenton process.Here,through structural design with density functional theory(DFT)calculations,Ce is predicted to enable the construction of coordinatively unsaturated metal centers(CUCs)in Prussian blue analogue(PBA),which can strongly adsorb H_(2)O_(2)and donate sufficient electrons for directly splitting the O-O bond to produceOH.Using a substitution-co-assembly strategy,binary Ce-Fe PBA is then prepared,which rapidly degrades sulfamethoxazole with the pseudo-first-order kinetic rate constant exceeding reported values by 1-2 orders of magnitude.Meanwhile,the photogenerated electrons reduce Fe(Ⅲ)and Ce(Ⅳ)to promote the metal valence cycle in CUCs and make sulfamethoxazole degradation efficiency only lose 6.04%in 5 runs.Overall,by introducing rare earth metals into transition metal-organic frameworks,this work guides the whole process for highly active CUCs from design and construction to mechanism exploration with DFT calculations,enabling ultrafast and stable photo-Fenton catalysis.

Functionalization of in vivo tissue-engineered living biotubes enhance patency and endothelization without the requirement of systemic anticoagulant administration

Vascular regeneration and patency maintenance,without anticoagulant administration,represent key developmental trends to enhance small-diameter vascular grafts(SDVG)performance.In vivo engineered autologous biotubes have emerged as SDVG candidates with pro-regenerative properties.However,mechanical failure coupled with thrombus formation hinder translational prospects of biotubes as SDVGs.Previously fabricated poly(ε-caprolactone)skeleton-reinforced biotubes(PBs)circumvented mechanical issues and achieved vascular regeneration,but orally administered anticoagulants were required.Here,highly efficient and biocompatible functional modifications were introduced to living cells on PB lumens.The 1,2-dimyristoyl-sn-glycero-3-phosphoethanolamine-N-methoxy(DMPE)-PEG-conjugated anti-coagulant bivalirudin(DPB)and DMPE-PEG-conjugated endothelial progenitor cell(EPC)-binding TPS-peptide(DPT)modifications possessed functionality conducive to promoting vascular graft patency.Co-modification of DPB and DPT swiftly attained luminal saturation without influencing cell viability.DPB repellent of non-specific proteins,DPB inhibition of thrombus formation,and DPB protection against functional masking of DPT’s EPC-capture by blood components,which promoted patency and rapid endothelialization in rat and canine artery implantation models without anticoagulant administration.This strategy offers a safe,facile,and fast technical approach to convey additional functionalization to living cells within tissue-engineered constructs.

Functionalization of PCL fibrous membrane with RGD peptide by a naturally occurring condensation reaction

Poly(e-caprolactone)(PCL)is widely adopted as an ingredient for tissue engineering scaffolds.To improve its cell affinity,in this study,we developed a new method to introduce bioactive RGD peptides onto the surface of PCL via condensation reaction between 2-cyanobenzothiazole(CBT)and D-cysteine.The PCL fibrous membranes were prepared by electrospinning,and RGD functionalization was characterized by fluorescence microscopy,scanning electron microscopy(SEM),X-ray photoelectron spectroscopy(XPS)and water contact angle(WCA).As expected,our results demonstrated the successful RGD immobilization on the surface of PCL.RGD modification improved the hydrophilicity of PCL,changing their WCA from 112.20°to38.35°.Cell adhesion,spreading and proliferation of 3T3fibroblasts were also enhanced.We therefore believe that the methods reported in this study was facile and effective for functional modification of the hydrophobic PCL scaffolds.The moderate reaction conditions are also suitable for covalent immobilization of bioactive molecules onto PCL.

Enhanced photocatalytic degradation of sulfamethoxazole by stable hierarchical Fe_(2)O_(3)/Co_(3)O_(4) heterojunction on nickel foam

A facile approach was successfully employed to prepare Fe_(2)O_(3)/Co_(3)O_(4)nanosheet arrays on nickel foams(Fe_(2)O_(3)/Co_(3)O_(4)@NF),which owned such advantages as narrow band gap energies and high separation rate of photoexcited electron-hole pairs.The combination of Fe_(2)O_(3)and Co_(3)O_(4)dramatically enhanced the photocatalytic activity towards sulfamethoxazole(SMZ)degradation,with the highest catalytic efficiency of k=0.0538 min^(−1),which was much higher than that of Fe_(2)O_(3)@NF(0.0098 min^(−1))and Co_(3)O_(4)@NF(0.0094 min^(−1)).The introduction of Ni foam could not only act as the support to anchor photocatalyst,but also work as the electron mediator to promote the transition of electron-hole pairs.Reactive species trapping experiments combined with electron paramagnetic resonance analysis confirmed^(·)O^(-)_(2)−was primarily responsible for SMZ degradation.Furthermore,Fe_(2)O_(3)/Co_(3)O_(4)@NF was effective and almost unaffected by inorganic cations and anions in aqueous solution.This study could provide a facile and promising path for the construction of self-supported metal oxide-based heterojunction with high efficiency and strong stability.

WaveLines:towards effective visualization and analysis of stability in power grid simulation

Closely related to the safety and stability of power grids,stability analysis has long been a core topic in the electric industry.Conventional approaches employ computational simulation to make the quantitative judgement of the grid stability under distinctive conditions.The lack of in-depth data analysis tools has led to the difficulty in analytical tasks such as situation-aware analysis,instability reasoning and pattern recognition.To facilitate visual exploration and reasoning on the simulation data,we introduce WaveLines,a visual analysis approach which supports the supervisory control of multivariate simulation time series of power grids.We design and implement an interactive system that supports a set of analytical tasks proposed by domain experts and experienced operators.Experiments have been conducted with domain experts to illustrate the usability and effectiveness of WaveLines.