Search results for "energy [jet]"
showing 10 items of 1760 documents
Design and characterization of bi-functional electrocatalytic layers for application in PEM unitized regenerative fuel cells
2010
Abstract Results concerning the development and characterization of bi-functional electrocatalytic layers for application in unitized regenerative fuel cells (URFCs) based on proton exchange membrane (PEM) technology are reported. Carbon-supported hydrophobic (10 wt.% of PTFE) Pt catalysts (40 wt.% of Pt), and Pt and Ir black powders of large specific areas have been synthesized. Their structure, morphology and electrochemical properties have been investigated using SEM, TEM, XRD analysis, and by measurements of polarization curves and cyclic voltammograms. Current–voltage curves have been recorded during water electrolysis and H 2 /O 2 fuel cell experiments to evaluate their performances a…
A Facile Strategy to Create Electrocatalysts of Highly Dispersive Ni–Mo Sulfide Nanosheets on Graphene by Derivation of Polyoxometalate Coordination …
2021
Fully Vacuum-Processed Wide Band Gap Mixed-Halide Perovskite Solar Cells
2017
Methylammonium lead mixed-halide perovskites MAPb(BrxI1–x)3 are promising materials for the preparation of tandem devices. When exposed to light, MAPb(BrxI1–x)3 segregates in iodide- and bromide-rich phases, limiting the achievable photovoltage and hence the attainable device efficiency. To date only solution-processed mixed-halide perovskites have been demonstrated. We present fully vacuum-deposited mixed-halide perovskite thin films with band gap of 1.72 and 1.87 eV, prepared by controlling the deposition rates of the different halide precursors. When used in thin-film devices, these materials lead to power conversion efficiencies of 15.9 and 10.5%, respectively, which are among the highe…
Photovoltaic Properties of a Porphyrin-Containing Polymer as Donor in Bulk Heterojunction Solar Cells With Low Energy Loss
2017
Investigation on lithium/polymer electrolyte interface for high performance lithium rechargeable batteries
1997
Abstract Performance data of several linear and cross-linked polymer electrolytes are reported and the electrochemical criteria for the selection of electrolytes to be used in electric vehicle lithium metal batteries are discussed. Further, laboratory lithium cells with LiMn2O4 composite cathode were tested to ascertain the effective viability of these polymer in solid-state batteries and preliminary results are reported. This study clearly demonstrates the importance of a broad-based electrochemical characterization in selecting an electrolyte for lithium metal batteries.
Cluster dirhenium(III) cis-dicarboxylates with α-amino acids ligands as mighty selective G4s binders.
2021
The synthesis of four dirhenium(III) cis-dicarboxylates with the α-amino acids residues Asp (I), Glu (II), Phe (III) and Tyr (IV) is presented. The G-quadruplex stabilization potential was evaluated by fluorescence resonance energy transfer - melting analysis. All derivatives show specific binding to c-kit1 quadruplex, while II and IV have also strong stabilization activity to HTelo21 quadruplex. At the same time, the compounds do not show any stabilization activity for ds26 DNA, which suggests unique mechanisms of molecular DNA recognition for these complexes.
Comparative analysis of the coordinated motion of Hsp70s from different organelles observed by single-molecule three-color FRET.
2021
Cellular function depends on the correct folding of proteins inside the cell. Heat-shock proteins 70 (Hsp70s), being among the first molecular chaperones binding to nascently translated proteins, aid in protein folding and transport. They undergo large, coordinated intra- and interdomain structural rearrangements mediated by allosteric interactions. Here, we applied a three-color single-molecule Forster resonance energy transfer (FRET) combined with three-color photon distribution analysis to compare the conformational cycle of the Hsp70 chaperones DnaK, Ssc1, and BiP. By capturing three distances simultaneously, we can identify coordinated structural changes during the functional cycle. Be…
Coil-bridge transition in a single polymer chain as an unconventional phase transition: theory and simulation.
2014
The coil-bridge transition in a self-avoiding lattice chain with one end fixed at height H above the attractive planar surface is investigated by theory and Monte Carlo simulation. We focus on the details of the first-order phase transition between the coil state at large height H ⩾ Htr and a bridge state at H ⩽ Htr, where Htr corresponds to the coil-bridge transition point. The equilibrium properties of the chain were calculated using the Monte Carlo pruned-enriched Rosenbluth method in the moderate adsorption regime at (H/Na)tr ⩽ 0.27 where N is the number of monomer units of linear size a. An analytical theory of the coil-bridge transition for lattice chains with excluded volume interact…
Straightforward synthesis of bioconjugatable azo dyes. Part 1: Black Hole Quencher-1 (BHQ-1) scaffold
2014
Abstract Azo dyes are currently used to quench the fluorescence of energy donors in bioassays through Forster resonance energy transfer (FRET) phenomenon. Common examples of such dark quenchers are DABCYL and the three members of Black Hole Quencher® (BHQ) family. Yet, only carboxylic acid and phosphoramidite derivatives of such azo dyes are presently commercially available. This Letter presents a straightforward synthesis method to novel bioconjugatable quenchers derived from BHQ-1 scaffold and equipped with a reactive group being either azido, terminal alkyne, or maleimide. The potential utility of the ‘clickable’ azido and thiol-reactive derivatives was notably demonstrated through the p…
Hetero-Telechelic Dye-Labeled Polymer for Nanoparticle Decoration
2009
The synthesis of poly(methyl methacrylate) (PMMA) exhibiting one fluorescent dye (Texas Red) and one methyl disulfide end group is described. It is shown that the latter end group enabled the exchange of both oleic amine on gold nanoparticles (AuNP) and of oleic acid on CdSe/ZnS quantum dots (QD), allowing for a phase transfer of both types of nanoparticles (NP) from hexane into dimethylformamide due to the solubility provided by the PMMA chains. For AuNP, a fluorescence quenching of the dye was found due to fluorescence resonance energy transfer (FRET) from the dye to the AuNP, while QDs caused a fluorescence enhancement by FRET from the QD to the attached dyes. Due to the hetero-telecheli…