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Small angle X-ray scattering from MCM-41 and its synthesis gels : optimisation of the synthesis parameters

We have found optimised conditions for alkaline synthesis of the large pore molecular sieve, MCM-41, by determining small angle X-ray scattering and adsorption isotherms from materials at various stages of the preparation. The presence of highly curved surfaces, sealed structures, and quasicrystalline hexagonal products coexisting with true MCM-41 are all detected by transmission electron microsco

Methane dynamics in the 36 Å mesopores of MCM-41 studied by neutron scattering

The capillary melting of methane adsorbed into the uniform parallel mesopores of the new silicate MCM-41 has been studied by neutron inelastic scattering and neutron quasielastic scattering at an energy resolution of about 80 microelectron volts. Differences from bulk methane in both the rotational melting and the solid to liquid transition have been identified. Rotational melting occurs at about

Multienzyme Cellulose Films as Sustainable and Self-Degradable Hydrogen Peroxide-Producing Material

The use of hydrogen peroxide-releasing enzymes as a component to produce alternative and sustainable antimicrobial materials has aroused interest in the scientific community. However, the preparation of such materials requires an effective enzyme binding method that often involves the use of expensive and toxic chemicals. Here, we describe the development of an enzyme-based hydrogen peroxide-pr

Self-assembly of amphiphilic polyoxometalates for the preparation of mesoporous polyoxometalate-titania catalysts

Amphiphilic polyoxometalate (POM) surfactants were prepared by covalently grafting double hydrophobic tails with chain lengths C12H25, C14H29, C16H33 or C18H37 onto the lacunary Wells-Dawson {P2W17O61} headgroup. The critical micelle concentrations (CMCs) of these novel surfactants in aqueous solutions were determined by conductivity, and micelle formation was studied by small angle neutron scatte

Deep eutectic solvent in water Pickering emulsions stabilised by cellulose nanofibrils

Deep eutectic solvent (menthol : dodecanoic acid) in water (30 : 70) emulsions stabilised with partially oxidised cellulose nanoparticles remained stable for 200 days at room temperature. Deep eutectic-based emulsions offer potential for non-aqueous reaction systems, chemical extraction, and controlled release. Pickering emulsions using polysaccharides are less toxic and more stable than surfactan

Thermal resilience of ensilicated lysozyme via calorimetric and in vivo analysis

Ensilication is a novel method of protein thermal stabilisation using silica. It uses a modified sol-gel process which tailor fits a protective silica shell around the solvent accessible protein surface. This, electrostatically attached, shell has been found to protect the protein against thermal influences and retains its native structure and function after release. Here, we report the calorimetr

Structural and chemical heterogeneity in ancient glass probed using gas overcondensation, X-ray tomography, and solid-state NMR

Rare ancient glasses have complex, multi-scale structures requiring more sophisticated and non-destructive pore characterisation techniques than usual. Homotattic patch models for nitrogen adsorption gave better fits to the isotherm data, more accurate void space descriptors, and also greater understanding of the underlying physical factors affecting adsorption, than standard BET. These homotattic

Mesoporous Silica Formation Mechanisms Probed Using Combined Spin-Echo Modulated Small-Angle Neutron Scattering (SEMSANS) and Small-Angle Neutron Scattering (SANS)

The initial formation stages of surfactant-templated silica thin films which grow at the air-water interface were studied using combined spin-echo modulated small-angle neutron scattering (SEMSANS) and small-angle neutron scattering (SANS). The films are formed from either a cationic surfactant or nonionic surfactant (C16EO8) in a dilute acidic solution by the addition of tetramethoxysilane. Previ

Antagonistic mixing in micelles of amphiphilic polyoxometalates and hexaethylene glycol monododecyl ether

Hypothesis: Polyoxometalates (POMs) are metal oxygen clusters with a range of interesting magnetic and catalytic properties. POMs with attached hydrocarbon chains show amphiphilic behaviour so we hypothesised that mixtures of a nonionic surfactant and anionic surfactants with a polyoxometalate cluster as headgroup would form mixed micelles, giving control of the POM density in the micelle, and whi

Scarring and selection effects on children surviving elevated rates of postneonatal mortality in sub-Saharan Africa

Infants in sub-Saharan Africa face adversity: Infections and undernutrition are major causes of infant deaths and can cause physiological damage with long-lasting adverse scarring effects on the human development of the survivors, for example, in terms of health and education. However, selective mortality of more vulnerable children at very high levels of adversity in early life can leave the surv

From skating rink to physics assignment - Viewing a photo from a mechanics perspective

Circular motion changes the perception of up and down. For a skater, the need to lean in towards the centre of an arc constitutes an embodiment of centripetal acceleration. This paper presents a discussion between a physicist and a high-school science teacher without previous physics studies at university level. The discussions started as part of a course assignment and focused on a photo of skate