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Thomas J. Neal; Andrew J. Parnell; Stephen M. King; Deborah L. Beattie; Martin W. Murray; Neal S. J. Williams; Simon N. Emmett; Steven P. Armes; Sebastian G. Spain; Oleksandr O. Mykhaylyk
partitioncoefficients, etc ; acrylates; composite polymers; hydrophilicity; hydrophobicity; nanoparticles; particle size; polyhydroxyethyl methacrylates; polymer nanocomposites; Show all 9 Subjects
Abstract:
... A range of amphiphilic statistical copolymers is synthesized where the hydrophilic component is either methacrylic acid (MAA) or 2-(dimethylamino)ethyl methacrylate (DMAEMA) and the hydrophobic component comprises methyl, ethyl, butyl, hexyl, or 2-ethylhexyl methacrylate, which provide a broad range of partition coefficients (log P). Small-angle X-ray scattering studies confirm that these amphiphi ...
partitioncoefficients, etc ; literature; models; municipal solid waste; physical properties; sorting; streams; waste management; Canada; Show all 9 Subjects
Abstract:
... Material recovery facilities and mechanical biological treatments play an important role in current municipal solid waste systems, by providing a way to separate the different municipal solid waste fractions according to their main physical properties. However, the composition of their outputs streams is directly impacted by the composition of the input stream and by the sequence of unit operation ...
partitioncoefficients, etc ; chromatography; duration; extracts; feeds; journals; mixtures; models; nootkatone; separation; solutes; trapping; traps; Show all 13 Subjects
Abstract:
... Trapping multiple dual mode (trapping MDM) is a preparative liquid-liquid chromatography (LLC) technique well-suited to difficult separations of intermediately-eluting components from similarly structured impurities. In this demonstrative study, a design approach for high process throughput is applied for the trapping MDM separation of a target component, nootkatone (NK), initially comprising 16.7 ...
partitioncoefficients, etc ; alcohols; hydrophobicity; models; prediction; solubility; solutes; Show all 7 Subjects
Abstract:
... Direct measurement of the n-octanol partition coefficients (KOW) for highly hydrophobic organic chemicals is extremely difficult because of the extremely low concentrations present in the water phase. n-Butanol/water partition coefficients (KBW) are generally much lower than KOW due to the increased solubility of solute in the alcohol saturated aqueous phase, and therefore become easier to measure ...
partitioncoefficients, etc ; calcite; calcium; carbonates; geochemistry; magnesium; seawater; yttrium; Show all 8 Subjects
Abstract:
... The reported partition coefficients of REE with calcite are reviewed and critically discussed. In some of the reported experimental sets, REE concentrations are found to be supersaturated with respect to individual REE₂(CO₃)₃ but never to REE(OH)₃. Although the solutions are unsaturated with respect to individual REY carbonates, REY including Y are incorporated in calcite surfaces, where they are ...
partitioncoefficients, etc ; acetonitrile; enthalpy; entropy; hydrocarbons; hydrophobicity; octanol; phase transition; reversed-phase high performance liquid chromatography; temperature; Show all 10 Subjects
Abstract:
... Phase ratio Φ for an high performance liquid chromatography (HPLC) column is a parameter defined as the ratio between the volume of the stationary phase Vₛ and the void volume of the column Vₘ. Together with the equilibrium constant K of the separation process, phase ratio is part of the retention factor k (k = KΦ). Although a considerable number of studies have been dedicated to the evaluation of ...
... The separation of desired monomers from a liquid-phase mixture of lignin depolymerization products is necessary to facilitate their upscaling and upgrading for industrial applications. One effective method to separate multiple liquid-phase products is countercurrent chromatography (CCC), which is a common liquid chromatography technique that separates target solutes based on differences in their p ...
partitioncoefficients, etc ; biotite; crystallization; fractionation; igneous rocks; mineralization; regression analysis; Show all 7 Subjects
Abstract:
... Despite Nb and Ta being considered as ‘geochemical twins’, most Ta mineral deposits are associated with muscovite-bearing peraluminous granites and related pegmatites (MPG), whereas significant Nb deposits are related to peralkaline to metaluminous A1-type granites and syenites as well as nepheline syenites. Metaluminous to peraluminous A2-type granites and syenites have a lower potential for rare ...
Oksana Tsendra; A. Daniel Boese; Olexandr Isayev; Leonid Gorb; Andrea Michalkova Scott; Frances C. Hill; Mykola M. Ilchenko; Victor Lobanov; Danuta Leszczynska; Jerzy Leszczynski
partitioncoefficients, etc ; adsorption; hydroxylation; trinitrotoluene; Show all 4 Subjects
Abstract:
... Adsorption energies of various nitrogen-containing compounds (specifically, 2,4,6-trinitrotoluene (TNT), 2,4-dinitrotoluene (DNT), 2,4-dinitroanisole (DNAn), and 3-nitro-1,2,4-triazole-5-one (NTO)) on the hydroxylated (001) and (100) α-quartz surfaces are computed. Different density functionals are utilized and both periodic as well as cluster approaches are applied. From the adsorption energies, ...
partitioncoefficients, etc ; coatings; dust; environmental health; exposure models; human health; per- and polyfluoroalkyl substances; products and commodities; volatile organic compounds; Show all 9 Subjects
Abstract:
... Per- and polyfluoroalkyl substances (PFAS) include a wide range of halogenated chemicals, which have been used as water- and stain-resistant coatings for consumer products and industrial purposes. PFAS are persistent in the environment and several are bioaccumulative, and thus relevant for human and environmental health. Given their pervasiveness, we need to understand how we are exposed to PFAS, ...
partitioncoefficients, etc ; adsorption; biochar; phenanthrenes; pollutants; remediation; sediments; soil; sorption isotherms; surfactants; Show all 10 Subjects
Abstract:
... Biochar is believed to be promising for soil contaminant stabilization due to its large adsorption capacity. However, study in sediment is rare, especially with the aging effect. In the present study, a plant biomass-derived biochar was added to phenanthrene polluted sediment, in order to investigate its performance in sediment remediation. During the incubation period of 60 days, it was observed ...
partitioncoefficients, etc ; alpha-amylase; circular dichroism spectroscopy; denaturation; microparticles; particle size; silica; Show all 7 Subjects
Abstract:
... Here, we report the implementation of α-amylase conjugated silica microparticles for improvement of α-amylase partitioning in a PEG–organic salt-based aqueous two phase system. A direct reduction method was employed for the synthesis of silica microparticles with simultaneous introduction of α-amylase. In this context, we synthesized three different silica α-amylase conjugated microparticles with ...
partitioncoefficients, etc ; UV filters; aquatic environment; diffusivity; kinetics; monitoring; samplers; silicone; Australia; Show all 9 Subjects
Abstract:
... In recent years, organic ultraviolet filters (UVFs) received considerable attention as a group of emerging contaminants, including in Australia where the use of UVFs is particularly relevant. Passive sampling using polymers has become widely used for routine monitoring of chemicals in the aquatic environment. Application of passive samplers for monitoring chemicals in the water relies on calibrati ...
... Countercurrent chromatography (or counter-current chromatography, CCC) is a unique support-free liquid-liquid partition chromatography. Since it was invented by Y. Ito in 1960s, CCC has been widely accepted and applied as popular separation and purification technique for natural and synthetic complex. However, up to date there is little study to address on hydrophobic and hydrophilic interactions ...
partitioncoefficients, etc ; countercurrent chromatography; equations; recycling; solutes; Show all 5 Subjects
Abstract:
... Closed-loop recycling dual-mode counter-current chromatography (CLR DM CCC) processes consist of two successive separation stages: separation of solutes in the recycling closed-loop with mobile x-phase and separation of solutes in the counter-current mode with mobile y-phase. Several variants of the implementation of this separation method can be developed: the closed-loop recycling stage may cons ...
partitioncoefficients, etc ; countercurrent chromatography; equations; models; solutes; Show all 5 Subjects
Abstract:
... Closed-loop recycling dual-mode counter-current chromatography (CLR DM CCC) includes two separation stages: 1 – closed-loop recycling separation of solutes with mobile x-phase (CLR CCC); 2 – separation of solutes with the mobile y-phase in the opposite flow direction. Previous analysis of CLR DM CCC separations has been limited to the ideal recycling model, which neglects extra-column dispersion. ...
partitioncoefficients, etc ; amino acids; ions; proteins; salts; Show all 5 Subjects
Abstract:
... Aqueous two-phase system (ATPS) containing salts has been used for protein purification and enrichment. However, it is unclear how proteins are partitioned in the top or bottom phases of the system. In this study, we demonstrate that the partition of proteins in salt-containing ATPS (SATPS) depends only on the relation between the protein-surface amino acids and the type of salt using SATPS. The p ...
partitioncoefficients, etc ; Bronsted acids; chemical bonding; polymerization; Show all 4 Subjects
Abstract:
... Correction for ‘Brønsted acid mediated covalent organic framework membranes for efficient molecular separation’ by Hongjian Wang et al., J. Mater. Chem. A, 2019, 7, 20317–20324. ...
partitioncoefficients, etc ; cosmetics; fatty acids; ingredients; micelles; molecular dynamics; prediction; sodium; solutes; sulfates; Show all 10 Subjects
Abstract:
... Sodium laureth sulfate (SLES) and fatty acids are common ingredients in many cosmetic products. Understanding how neutral and charged fatty acid compounds partition between micellar and water phases is crucial to achieve the optimal design of the product formulation. In this paper, we first study the formation of mixed SLES and fatty acid micelles using molecular dynamics (MD) simulations. Micelle ...
partitioncoefficients, etc ; countercurrent chromatography; ethyl acetate; heptane; methanol; models; prediction; solutes; solvation; solvents; Show all 10 Subjects
Abstract:
... The method development of liquid-liquid chromatography, either countercurrent chromatography or centrifugal partition chromatography, is slowed down by the selection of the biphasic solvent system that constitutes its column. This paper introduces a classification of 19 solvent systems, including the most popular systems based on heptane/ethyl acetate/methanol/water, some non-aqueous systems and s ...