By covalently linking an azobenzene photoswitch across the binding groove of a PDZ domain, conformational transition, similar to one occurring upon ligand unmodified can be initiated on picosecond timescale by laser pulse. The protein structures have been characterized in two states through NMR spectroscopy and transition between them ultrafast IR molecular dynamics simulations. opens 100-ns highly nonexponential manner, simulations suggest that process is governed rearrangement water...

The folding of a pH-sensitive leucine zipper, that is, GCN4 mutant containing eight glutamic acid residues, has been investigated. A pH-jump induced by caged proton (o-nitrobenzaldehyde, oNBA) is employed to initiate the process, and time-resolved IR spectroscopy amide I band used probe it. experiment carefully designed minimize buffer capacity sample solution so large pH jump can be achieved, leading transition from completely unfolded folded state with single laser shot. In order eliminate...

With a combination of transient pump-probe IR spectroscopy and ab initio molecular dynamics, the controversial pico- nanosecond steps o-nitrobenzaldehyde (oNBA) photoreaction have been investigated in aqueous solution. In this way, measured reaction kinetics complemented with an atomistic picture reactive events as obtained unbiased simulations explicit solvent. Our results allow for detailed description oNBA proton photorelease, process fundamental importance relevant to use cage many...

Promising results were recently reported for hierarchical ion-exchange membranes, fabricated by the UV crosslinking of a thin functional coating on porous substrate, model NaCl solution demineralization electrodialysis (ED). Hierarchical anion-exchange membranes (hAEMs) have never been tested with complex solutions to demonstrate their potential use in biofood industry. The impact three different densities (EbN-1, EbN-2 and EbN-3) performances whey ED was investigated compared commercial...

Proton transfer reactions, including acid-base recombination, are commonly considered to occur 'nearly instantaneously'. However, their actual time scales may stretch far into the microsecond range, as reactions diffusion controlled and concentrations low near neutral pH. The interplay of competing bases in pH relaxation is illustrated using a model system consisting o-nitrobenzaldehyde (oNBA) proton cage acetate ions hydroxyl bases. kinetically behavior leads highly counterintuitive states,...

This work presents a versatile chemistry platform for the fabrication of hierarchical cation and anion exchange membranes (hCEMs hAEMs) with tuneable transport properties. A strong focus was put onto developing cost-effective fabricated through sustainable easily scalable process, performance at least as good industry standard materials. Hierarchical ion were by coating UV crosslinking an acrylic ionomer on top PVC-SiO2 porous substrate. Membrane samples different density tested application...

Acid–base systems are commonly expected to equilibrate on a time scale much faster than any other chemical reaction, so their composition can be deduced from the corresponding pKa or pKb values. In pH-jump experiment done multi-acid/base pair system, it was found that takes tens of microseconds before an equilibrium is established. Within time, system kinetically driven, reaching surprising states very different its final equilibrium; for example, carboxylate groups were protonated in...

The membrane is a crucial component of Zn slurry–air flow battery since it provides ionic conductivity between the electrodes while avoiding mixing two compartments. Herein, six commercial membranes (Cellophane™ 350PØØ, Zirfon®, Fumatech® PBI, Celgard® 3501, 3401 and 5550) were first characterized in terms electrolyte uptake, ion zincate crossover, tested battery. peak power density employing was found to depend on in-situ cell resistance. Among them, using 3501 membrane, with area...

Hierarchical cation-exchange membranes (hCEMs) fabricated by blade coating and UV crosslinking of ionomer on top a porous substrate demonstrated promising results in performing NaCl demineralization. In the food industry, complex solutions are used hCEMs were never investigated before for these applications. The performances two different chemistries (urethane acrylate based: UL, acrylic acid EbS) three degrees (UL5, UL6, UL7 UL formulations, EbS-1, EbS-2, EbS-3 EbS formulations) formulated....

Voltammetric reductive desorption, scanning tunneling microscopy (STM) and surface-enhanced Raman scattering (SERS) were used to determine the composition structure of mixed, two-component monolayers sodium 2-mercaptoetanosulfonate (MES) mercaptoundecanol (MUL) on silver gold supports. Monolayers prepared by self assembling from ethanolic solutions varying composition. Preferred adsorption MUL was found in electrochemical experiments Au(111). The presence two well-separated desorption peaks...

This work presents a systematic approach to formulating UV curable ionomer coatings that can be used as ion-exchange membranes when they are applied on porous substrates. Ion-exchange fabricated in this way cost-effective alternative perfluorosulfonic acid membranes, such Nafion and similar thin film membranes. Hierarchically structured coated find applications for energy storage conversion (organic redox flow batteries artificial photosynthesis cells) separation processes (electrodialysis)....

Composite anion-exchange membranes (AEMs) consisting of a porous substrate and vinyl imidazolium poly(phenylene oxide) (VIMPPO)/acrylamide copolymer layer were fabricated in straightforward process, for use redox flow batteries. The was coated with mixture VIMPPO acrylamide monomers, then subsequently exposed to UV irradiation, order obtain radically cured ion-exchange coating. Combining low-value reagents allowed significantly reduce the amount synthesized ionomer used fabricate mem- brane...

This paper presents a novel, cost-effective approach to the fabrication of composite anion exchange membranes (AEMs). Hierarchical AEMs have been fabricated by coating porous substrate with an interpenetrating polymer network (IPN) layer where poly(vinylpyrrolidone) (PVP) is immobilized in crosslinked matrix. The IPN matrix was formed UV initiated radical crosslinking mixture acrylamide-based monomers and acrylic resins. compared commercial material (Fumatech FAP 450) terms ionic transport...

Abstract Industrial application of ion‐exchange membranes, the key component many electro‐membrane processes, is often hindered due to their high cost—result complex fabrication methods and use highly engineered precursors. As an alternative conventional anion‐exchange membrane (AMX), this study focuses on cation‐coated filtration membranes (CCFM‐Type 1 CCFM‐Type 2) by depositing a thin layer crosslinked branched polyethyleneimine (PEI)‐based ionomer top porous substrate. The commodity...

pH can be used to impact the folding equilibrium of peptides and proteins. This fact is utilized, similarly temperature jumps, in jump experiments employing laser time-resolved spectroscopy study function structural dynamics these molecules. Here application jumps was investigated. Experiments with poly-L-glutamic acid alpha-helix formation shown critical aspects yielded direct information about kinetics monitored amide I IR band.