Multiple factors influencing high-purity indium electrolytic refining

The effects of various contaminants in the electrolytic refinement of indium were investigated using a glow discharge mass spectrometer(GDMS).The effects of several factors such as the indium ion(In3+)concentration,the sodium chloride(NaCl)concentration,the current density,the gelatin concentration,the pH,and the electrode distance,were examined.Significant variations in impurity levels concerning gelatin concentration were observed.Both the gelatin and In3+concentration were moderately positively correlated with the Pb content.The Sb concentration was associated positively with the NaCl concentration,while the Ti concentration had an adverse correlation with the NaCl concentration.The Bi element content was positively linked to the electrode distance.As the current density increased,Cu,Pb,and Bi impurities initially rose and then eventually declined.Notably,a critical current density of 45 A·m^(-2) was identified in this behavior.

Structure-function relationship of antimicrobial peptide cathelicidin Pc-CATH1

Cathelicidin Pc-CATH1 is a cathelicidin-derived myeloid antimicrobial peptide identified from Phasianus colchicus with strong antimicrobial activity against most of bacteria and fungi tested,including the clinically isolated(IS)drug-resistant strains.Considering the uniform distribution of net positive charge in both C-and N-terminus sequence of cathelicidin Pc-CATH1 and most of hydrophobic amino acid(aa)residues positioned in middle of the sequence,the antimicrobial peptide was used to investigate the structure-function relationship by truncating gradually N-or C-terminus amino acid residue.More than 10 modified peptide homo-logues(20-26 aa length)of cathelicidin Pc-CATH1 were found to keep strong antimicrobial abilities.The possible relationships between bioactivities including antimicrobial and hemolytic abilities,components of secondary structure,hydrophobicity,amphipathicity,net charge,and sequence length were investigated.The current work provided suggestions for structural and functional modification of linear,α-helical antimicrobial peptides containing no disulfided bridges.

MOF-derived Cu embedded into N-doped mesoporous carbon as a robust support of PdAu nanocatalysts for ethanol electrooxidation

Metal-organic frameworks(MOFs)h ave attracted widespread attention due to their large surface area and porous structure.Rationally designing the nanostructures of MOFs to promote their application in ethanol electrooxidation is still a challenge.Here,a novel Cu-NCNs(Cu-nitrogen-doped carbon nanotubes)support was synthesized by pyrolysis of melamine(MEL)and Cu-ZIF-8 together,and then,Pd-Au nanoalloys were loaded by sodium borohydride reduction method to prepare PdAu@Cu-NCNs catalysts.The generating mesoporous carbon with high specific surface area and favorable electron and mass transport can be used as a potential excellent carrier for PdAu nanoparticles.In addition,the balance of catalyst composition and surface structure was tuned by controlling the content of Pd and Au.Thus,the best-performed Pd_(2)Au_(2)@Cu-NCN-1000-2(where 1000 means the carrier calcination temperature,and 2 means the calcination constant temperature time)catalyst exhibits better long-term stability and electrochemical activity for ethanol oxidation in alkaline media(4.80 A·mg^(-1)),which is 5.05 times higher than that of commercial Pd/C(0.95 A·mg^(-1)).Therefore,this work is beneficial to further promoting the application of MOFs in direct ethanol fuel cells(DEFCs)and can be used as inspiration for the design of more efficient catalyst support structures.

Enhanced ethanol oxidation over Pd nanoparticles supported porous graphene-doped MXene using polystyrene particles as sacrificial templates

Fabrication of superior catalytic performance palladium-based catalysts with affordable cost is the key to develop direct ethanol fuel cell.Herein,Pd-decorated three-dimensional(3D)porous constructed from graphene oxide(GO)and MXene combining with polystyrene(PS)particles as sacrificial templates(Pd/GO-MXene-PS)to elevate the catalytic performance for ethanol oxidation was proposed.The 3D porous interconnected structure of Pd/GO-MXene-PS was characterized by scanning electron microscope(SEM),transmission electron microscope(TEM)and Brunner−Emmet−Teller(BET).By optimizing the doping ratio of MXene to GO,the mass activity of Pd/GO_(5)-MXene_(5)-PS(2944.0 mA·mg^(−1))was 3.0 times higher than that of commercial Pd/C(950.4 mA·mg^(−1))toward ethanol oxidation in base solution.Meanwhile,the rotating disk electrode(RDE)results demonstrated that Pd/GO5-MXene5-PS had a faster kinetics of ethanol oxidation.The enhanced ethanol oxidation over Pd/GO5-MXene5-PS could attribute to the excellent 3D interconnected porous structure,large surface area,good conductivity and homogeneous Pd distribution.This work provided a new idea for creating 3D porous MXene composite materials in electrocatalysis.

Structural Basis for Ubiquitin Recognition by a Novel Domain from Human Phospholipase A2 Activating Protein

Ubiquitin (Ub) is an essential modifier conserved in all eukaryotes from yeast to human. Phospholipase A2 activating protein (PLAA), a mammalian homolog of yeast DOA1/UFD3.