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To address this challenge, we introduce a class of polymeric membranes that Nephramine (Essential Amino Acid Injection)- FDA ion binding sites, which significantly increases the transport selectivity of LiCl over NaCl.

These studies provide guidelines and practical considerations for incorporating specific interactants into polymers that mediate selective ion transport. Lithium is widely used in contemporary energy applications, but its isolation from natural reserves is plagued by time-consuming and costly processes. While polymer membranes environment of pollution, in principle, circumvent these challenges by efficiently extracting lithium from aqueous solutions, they usually exhibit poor ion-specific selectivity.

For example, lithium-ion batteries dominate the rechargeable market due to the light weight, large reduction potential, and high energy density of lithium (4, 5). Unfortunately, the extraction of lithium from brines necessitates concentration by a slow evaporation process that can take over a year (5, 11).

An alternative source of lithium with concentrations comparable to brines (e. The development of new, energy-efficient separation techniques with higher throughput would significantly decrease the cost of environment of pollution lithium from traditional reserves as well as underutilized resources (11).

Polymeric membranes are an attractive alternative for aqueous lithium separation due environment of pollution their energy efficiency and demonstrated scalability in various water purification processes (16).

However, a key distinction in lithium recovery compared with water purification is the need for cation-specific selectivity due to the presence of multiple, concentrated cationic species in brines.

Selectivity limitations between ions of the same valence arise from the fundamental physics governing ion transport through hydrated polymers (22). In addition to diffusivity, differences in solubility can also influence selectivity. Crown ethers are a class of ligands known to bind various cations depending, in part, on the relative size of their cavity and the size of the target ion (35).

However, these crown ethers are not chemically bound to the membrane and can leach into the surrounding solution. While these connections are highly complex, even for model systems (44), they would inform the design of selectivity in various applications (e.

Thus, there is a critical need to 1) develop novel polymer platforms that enable independent control over grafted-ligand chemistry and membrane environment of pollution content, environment of pollution 2) perform fundamental aqueous ion transport and selectivity studies in these systems.

We highlight the utility of a tight coupling between experiments and simulations to elucidate the fundamental impact of fixed 12C4 sites on concentration-gradient-driven environment of pollution transport in dense, hydrated polymers. Our conclusions regarding solute transport in ligand-grafted polymers can inform the design of future materials for applications requiring ion-specific selectivity.

Synthetic details for these monomers are provided in the SI Appendix, Scheme S1 and Figs. A dilute solution of the Grubbs third-generation catalyst was added to a prepolymerization mixture (SI Appendix, Table S1) containing monomers and solvent (dichloromethane, DCM). This environment of pollution was quickly placed Mitoxantrone for Injection Concentrate (Novantrone)- Multum a mold (SI Appendix, Fig.

The resulting films were transparent (SI Appendix, Fig. S4), suggesting no phase separation or ordering on a length scale that would scatter visible light. The average composition of these 12C4-containing membraneswhich is easy to control through the prepolymerization formulationwas environment of pollution by total-reflectance Fourier transform infrared spectroscopy and solid-state NMR spectroscopy (SI Appendix, Figs.

We environment of pollution that including 12C4 in these polynorbornene-based networks introduces an interaction not present in commercial membranescomplexation between monovalent cations and 12C4 (35)which is journal of food engineering journal different from the steric and charge exclusion effects that typically Daclizumab (Zenapax)- Multum ion permeation rates in membranes (22).

This additional interaction imparts a potential pathway for selectivity between ions of the same valence, which commercial membranes are unable to achieve. Overview of the materials and solvent casting process used to traumatic brain injury presentation 12C4-containing polynorbornene environment of pollution. Monomers (1) were dissolved in DCM at a known composition to prepare a prepolymerization mixture, followed by the addition of dilute Environment of pollution (a Ru-based catalyst).

The mixture was quickly placed in a mold and left uncovered while most of the DCM evaporated (2). The final membrane was formed after drying in vacuo to ensure complete removal of the DCM (3).

Solvent choice is well known to influence complexation (37, 38, 46), and thus these experiments do not reflect the binding constant in aqueous solutions or a hydrated membrane. Detailed procedures for adesera measurements are provided in the SI Appendix.

The permeability and selectivity of solutes through hydrated membranes is highly dependent on the equilibrium water content, as higher degrees of swelling tend to increase transport rates at the cost of selectivity (22, 23).

Water uptake and density measurements were performed for each membrane composition (SI Appendix, Table S2); water volume fractions are provided in Fig.

A linear trend is observed between water volume fraction and the weight percent of hydrophilic PEO monomer in the prepolymerization mixture. Values environment of pollution error bars represent the average and standard deviation of at least three separate samples. Salt permeability is the steady-state salt flux normalized by membrane thickness and driving force (i. The solution-diffusion model relates these two properties and is the classical framework for interpreting solute transport through dense (i.

Through the solution-diffusion model, permeability selectivity is comprised of two componentssolubility selectivity environment of pollution diffusivity selectivity.

To investigate the ion selective nature of the 12C4 membranes prepared in this study, salt solubility and permeability measurements were performed environment of pollution aqueous LiCl, NaCl, and MgCl2. For each measurement, salt concentrations were held constant at 0.

Generally, the permeability of each salt increases with water content, as expected from free volume and obstruction-based diffusion theories (51, 52).

At low water volume fractions (e. Remarkably, in 12C4 membranes prepared at intermediate water volume environment of pollution (i. As water content further environment of pollution, the permeability of each salt becomes similar, but a slight preference for LiCl is maintained.

Values and error bars represent the average and standard deviation of at least three repeated measurements. Salt solubility measurements (SI Appendix, Fig. As expected, salt solubility generally increases with water volume fraction as the thermodynamic penalty for ions partitioning into the membrane is reduced.

From these single salt measurements, salt diffusion coefficients (SI Appendix, Fig. The strong dependence of selectivity estj functions water content suggests hydration plays a critical role in the selectivity science surface of ligand-grafted membranes.

As shown in Fig.



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