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Temperature dependent specific ion effects in mixed salt environments on a thermoresponsive poly(oligoethylene glycol methacrylate) brush

The temperature induced swelling/collapse transition of poly(oligoethylene glycol methacrylate) (POEGMA) brushes has been investigated in electrolyte solutions comprised of multiple anions. The behaviour of a POEGMA brush in mixed salt environments of potassium acetate (KCH3COO, causes collapse) and thiocyanate (KSCN, causes swelling), two ions at opposite ends of the Hofmeister series, has been m

Combined experimental and theoretical study of weak polyelectrolyte brushes in salt mixtures

The swelling behavior of a hydrophobic poly(2diisopropylamino)ethyl methacrylate (PDPA) brush immersed in aqueous solutions of single and mixed salts has been investigated using ellipsometry and numerical self-consistent field (nSCF) theory. As a function of solution ionic strength, the osmotic and salted brush regimes of weak polyelectrolyte brushes as well as substantial specific anion effects i

Influence of molecular weight on PNIPAM brush modified colloidal silica particles

The effect of molecular weight and temperature on the phase transition and internal structure of poly(N-isopropylacrylamide) brush modified colloidal silica particles was investigated using dynamic light scattering (DLS) and small angle neutron scattering (SANS) between 15 and 45 °C. Dry particle analysis utilising transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FT

Specific ion effects on thermoresponsive polymer brushes: Comparison to other architectures

Thermoresponsive polymers have received significant research attention as smart materials with particular interest in biomedical applications. The composition and architecture are known to strongly influence the thermoresponsive properties of the materials. For example, the strong overlap of end-grafted polymer chains in polymer brushes leads to a broader collapse transition relative to linear ung

The role of copolymer composition on the specific ion and thermo-response of ethylene glycol-based brushes

Thermoresponsive ethylene glycol based comb-polymer brushes were studied as a function of copolymer composition in aqueous electrolyte solutions. Homopolymer poly oligo(ethylene glycol) methyl ether methacrylate (POEGMA300) and statistical copolymer brushes with 60 mol% OEGMA300 and 40 mol% (di(ethyleneglycol) methyl ether methacrylate) (MEO2MA) underwent a monotonic swollen to collapsed transitio

Specific anion effects on the internal structure of a poly (N-isopropylacrylamide) brush

The effect of anion identity and temperature on the internal nanostructure of poly(N-isopropylacrylamide) brushes were investigated using neutron reflectometry (NR), atomic force microscopy (AFM), and quartz crystal microbalance with dissipation monitoring (QCM-D). NR and QCM-D measurements showed that addition of strongly kosmotropic acetate anions shifted the lower critical solution temperature

Specific ion modulated thermoresponse of poly (N-isopropylacrylamide) brushes

The influence of specific anions on the equilibrium thermoresponse of poly(N-isopropylacrylamide) (pNIPAM) brushes has been studied using in situ ellipsometry, quartz crystal microbalance with dissipation (QCM-D) and static contact angle measurements between 20 and 45 °C in the presence of up to 250 mM acetate and thiocyanate anions in water. The thickness and changes in dissipation exhibited a br

Anion-specific effects on the behavior of pH-sensitive polybasic brushes

The anion-specific solvation and conformational behavior of weakly basic poly(2-dimethylamino)ethyl methacrylate (poly(DMA)), poly(2-diethylamino)ethyl methacrylate (poly(DEA)), and poly(2-diisopropylamino)ethyl methacrylate (poly(DPA)) brushes, with correspondingly increasing inherent hydrophobicity, have been investigated using in situ ellipsometric and quartz crystal microbalance with diss

Hydrophobic effects within the dynamic pH-response of polybasic tertiary amine methacrylate brushes

The solvation and swelling behaviour of three dialkylaminoethyl methacrylate polymer brushes, of varying hydrophobicity, have been investigated using a combination of in situ ellipsometry and a quartz crystal microbalance with dissipation (QCM-D). At low pH the tertiary amine groups of the three polymers are protonated and all three brushes are significantly solvated and swell by adopting an exten

Critical salt effects in the swelling behavior of a weak polybasic brush

The swelling behavior of poly(2-(diethylamino)ethyl methacrylate) (PDEA) brushes in response to changes in solution pH and ionic strength has been investigated. The brushes were synthesized by ARGET ATRP methodology at the silica–aqueous solution interface via two different surface-bound initiator approaches: electrostatically adsorbed cationic macroinitiator and covalently anchored silane-bas

The coherent electromagnetic field and the effect of the pair distribution function

The effect of two different pair correlation functions, used to model multiple scattering in a slab filled with randomly located spherical particles, is investigated. Specifically, the Percus-Yevick approximation is employed and a comparison with the simple hole correction is made. The kernel entries of the hole correction have an analytic solution, which makes the numerical solution of the integr

Weakened resilience of benthic microbial communities in the face of climate change

Increased ocean temperature associated with climate change is especially intensified in coastal areas and its influence on microbial communities and biogeochemical cycling is poorly understood. In this study, we sampled a Baltic Sea bay that has undergone 50 years of warmer temperatures similar to RCP5-8.5 predictions due to cooling water release from a nuclear power plant. The system demonstrated

Which architectural style makes an attractive streetscape? Aesthetic preferences among city centre managers

Rational design based on aesthetic principles from the 1930s dominates contemporary architecture and property development, contributing to a homogenous urban landscape. The aim of this paper is to examine how professionals involved in city centre development value different architectural styles. Based on a sample of 109 respondents, measuring the architectural preferences of city centre managers,

Working With Nature to Solve Societal Problems

Are you worried about the climate and biodiversity crises and related events like heavy rainfalls and floods, high carbon emissions, sudden heat waves, or loss of species? Are you already doing something to help solve these problems? To reduce flood risks, we can give rivers more space by reconnecting floodplains. To store carbon and help to slow down climate change, we can protect and establish w

Förändrade resvanor och mobilitetstjänster - En kunskapsöversikt

Denna rapport tittar närmare på de förändringarna i resvanor som skett de senaste årtiondena, inklusive en kort historisk utblick, vilka har identifierats i transportlitteraturen. Rapporten undersöker även möjligheten till innovation kopplat till transportslag och till mobilitetstjänster med syfte att svara upp till befintliga och framtida resebehov.Specifikt presenteras några möjliga svar till fr