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Chemically surface-modified carbon nanoparticle carrier for phenolic pollutants : Extraction and electrochemical determination of benzophenone-3 and triclosan

Chemically surface-modified (tosyl-functionalized) carbon nanoparticles (Emperor 2000 from Cabot Corp.) are employed for the extraction and electrochemical determination of phenolic impurities such as benzophenone-3 (2-hydroxy-4-methoxybenzophenone) or triclosan (5-chloro-2-(2,4-dichlorophenoxy)phenol). The hydrophilic carbon nanoparticles are readily suspended and separated by centrifugation prio

Growth and characterization of mesoporous silica films

The synthesis of surfactant-templated silicate materials has developed rapidly over the past decade. The uniform controlled pore sizes created in the amorphous silicate framework by this method show promise as catalyst supports, sensors, filtration membranes and in a variety of optoelectronic applications. Formation of these materials in a thin-film or membrane geometry is therefore an active area

Shear and salt effects on the structure of MCM-41 synthesis gels

Orientational ordering under shear was observed for some precursor gels for the synthesis of the hexagonal mesoporous silica MCM-41 in the presence of high KBr concentrations. The presence of KBr disrupted the formation of the first-order MCM-41 diffraction peak dependent upon KBr concentration. Synthesis gels which formed good quality MCM-41, but with no added KBr salt, were not oriented by stron

Structure and dynamics of hydrogen sorption in mesoporous MCM-41

Adsorption isotherms taken at temperatures ranging from 20 to 77 K show a large pore volume and surface area of 980 m2 g-1 for the physical adsorption of molecular hydrogen on MCM-41. The adsorbed hydrogen behaves more like a solid than a liquid and isosteric heats of adsorption reveal a heterogenous surface. The evaporation behaviour of the adsorbed hydrogen indicates that the hexagonally packed

A tale of two mechanisms : comparing mesostructure formation in cationic and non-ionic surfactant-templated silicas

The formation of surfactant templated silica films at the air-solution interface has been investigated in situ using a number of time-resolved surface-sensitive and bulk sensitive techniques. Results from templating solutions prepared using a non-ionic surfactant (C16EO8) are compared to those obtained when a cationic surfactant (CTAB) is used. In both cases specific solution phase interactions dr

Measurement of the Adsorption of Cytochrome c onto the External Surface of a Thin-Film Mesoporous Silicate by Ellipsometry

The measurement of adsorption of cytochromes c onto the external surfaces of a thin film mesoporous silicates (MPS) supported by silicon wafers was discussed. Adsorption in a multilayered system consisting silicon, SiO 2, MPS, and adsorbed proteins was analyzed using ellipsometry. Synthesis of MPS thin films on 0.5 mm thick silicon wafers was done using a dip-coating alcohol vaporization method. I

Assembly of nonionic-anionic co-surfactants to template mesoporous silica vesicles with hierarchical structures

Mesoporous silica vesicles (MSV) with a hierarchical structure were developed using triblock copolymer Pluronic P103 and anionic surfactant sodium dodecyl sulfate (SDS) as a co-surfactant in the present of an inorganic salt, sodium fluoride (NaF). To some extent, variation in the particle size and vesicle cavity diameter can be achieved by adjusting the anionic-nonionic surfactant molar ratio. An

Thin-film modified electrodes with reconstituted cellulose-PDDAC films for the accumulation and detection of triclosan

A strategy for the formation of thin reconstituted cellulose films (pure or modified)) with embedded receptors or embedded ion-selective components is reported. Cellulose nanofibril ribbons from sisal of typically 3-5 nm diameter and 250 nm length are reconstituted into thin films of typically 1.5-2.0 μm thickness (or into thicker free-standing films). Cellulose and cellulose nanocomposite films a

Effect of micelle composition on the formation of surfactant-templated polymer films

Surfactant-templated polymer films prepared from polyethylenimine (PEI), cetyltrimethylammonium bromide (CTAB), and octaethylene glycol monohexadecyl ether (C16E8) were examined and the effect of increasing the percentage of nonionic surfactant in the micelles measured using both surface and bulk-sensitive techniques. It was found that there is a strong interaction between CTAB and C16E8, although

Microcalorimetric study of ammonia chemisorption on H3PW 12O40 supported onto mesoporous synthetic carbons and SBA-15

Keggin tungstophosphoric acid supported onto mesoporous and meso-microporous materials was studied by ammonia microcalorimetry. Experiments were performed at high and low temperatures to separate the contributions of chemisorpdon and physisorption, low-temperature data being potentially important for the ambient temperature purification processes. Analysis of thermokinetic data obtained from heat

Fundamental studies of gas sorption within mesopores situated amidst an inter-connected, irregular network

There has been little, or no, direct testing of theories of gas sorption within particular pores situated amidst a highly inter-connected pore network. The concept of thermodynamically independent pores within networks has also been challenged. In this work, a novel integrated nitrogen sorption and mercury porosimetry technique has been used to deconvolve the condensation and evaporation processes

Free-standing ordered mesoporous silica films synthesized with surfactant-polyelectrolyte complexes at the air/water interface

Solid cetyltrimethylammonium bromide (CTAB) and polyethylenimine (PEI) films self-assemble at the air/water interface. Small angle X-ray scattering (SAXS) measurements show that dried films maintain the same ordered mesostrueture as the films at the air/water interface, and here the effects of PEI concentration and cross-linker (CL) on film mesostrueture were investigated. Free-standing silica fil

Formation of mesostructured thin films at the air/water interface

Mesostructured thin films are known to form at the interface between either air or a solid surface and a dilute acidic solution containing the silica precursor, and surfactant template. These films are transparent, and, when grown at the air/solution interface, self-supporting. We have been studying the formation processes of these films to try to understand and thus control the formation of both

Determination of the percolation properties and pore connectivity for mesoporous solids using NMR cryodiffusometry

Using a model disordered mesoporous solid with a spatial arrangement of pore sizes analogous to a macroscopic 'ink-bottle', it has been shown that the hysteresis observed in NMR cryoporometry can be deconvoluted into separate single pore and pore-blocking contributions. The suggestion of pore-blocking effects has been confirmed using PFG NMR. Hence, percolation theory has been used, for the first

Modeling the fractal growth of templated, mesoporous silica films

Brewster angle micrographs have been obtained of the development of a silica film grown at an air-water interface with use of the surfactant template cetylpyridinium chloride. The micrograph images showed that the growing silica film exhibited complex, fractal-like patterns. These images have been analyzed to determine the values of the fractal dimension and lacunarity, and the forms of the autoco

Late effects in patients with mantle cell lymphoma treated with or without autologous stem cell transplantation

Studies on late effects in patients with mantle cell lymphoma (MCL) are becoming increasingly important as survival is improving, and novel targeted drugs are being introduced. However, knowledge about late effects is limited. The aim of this population-based study was to describe the magnitude and panorama of late effects among patients treated with or without high-dose chemotherapy with autologo

MAC-1 marks a quiescent and functionally superior HSC subset during regeneration

Mouse hematopoietic stem cells (HSCs) have been extensively defined both molecularly and functionally at steady state, while regenerative stress induces immunophenotypical changes that limit high purity isolation and analysis. It is therefore important to identify markers that specifically label activated HSCs to gain further knowledge about their molecular and functional properties. Here, we asse

Exercise is associated with younger methylome and transcriptome profiles in human skeletal muscle

Exercise training prevents age-related decline in muscle function. Targeting epigenetic aging is a promising actionable mechanism and late-life exercise mitigates epigenetic aging in rodent muscle. Whether exercise training can decelerate, or reverse epigenetic aging in humans is unknown. Here, we performed a powerful meta-analysis of the methylome and transcriptome of an unprecedented number of h

Regional clozapine, ECT and lithium usage inversely associated with excess suicide rates in male adolescents

Advanced psychiatric treatments remain uncertain in preventing suicide among adolescents. Across the 21 Swedish regions, using nationwide registers between 2016–2020, we found negative correlation between adolescent excess suicide mortality (AESM) and regional frequencies of clozapine, ECT, and lithium (CEL) usage among adolescents (β = −0.613, p = 0.0003, 95% CI: −0.338, −0.889) and males (β = −0