cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.5286/isis.e.rb1520109
title: Oxide Ion Disorder in Rhombohedral Bismuth Neodymium Oxide Electrolytes

description: Materials that exhibit high oxide ion conductivity are of interest with a view to their application in solid oxide fuel cells, gas sensors and gas separation membranes. A study of oxide ion distribution in a highly conducting neodymium substituted bismuth oxide based solid electrolyte system is proposed. This system exhibits a layered structure and previous studies have revealed significant positional disorder in the oxide ions close to the inter-layer space. This study aims to use total neutron scattering analysis of representative compositions in the bismuth neodymium oxide system to examine the compositional and thermal variation of oxide ion distribution, including Reverse Monte Carlo analysis of total neutron scattering data. These studies will be combined with parallel electrical and modelling studies to reveal details of the conductivity mechanism in this system.
DOI: 10.5286/isis.e.rb1520208
title: Quasi-elastic neutron study of the organic cation dynamics in the halide perovskite CH3NH3PbI3 for PV applications

description: Solar cells based on a layer of halide perovskite have recently seen rapid increases in efficiency, with certified values in excess of 20%.  The prototypical material of this class is the methyl-ammonium-containing halide perovskite CH3NH3PbI3.  Very recently, the phase transitions and dynamic disorder of this structure, which has been extensively studied since the eighties, have come under renewed scrutiny, since they appear to be related to key PV performance parameters. Here, we propose to study for the first time the dynamics of the CH3NH3 organic molecule via quasi-elastic neutron scattering, on OSIRIS. This will allow the detailed study of the CH3NH3 reorientation and its effect on the phase transitions and symmetry of the low temperature phases. Additionally we propose the measurement of a fully deuterated sample to investigate dynamical correlations between CH3NH3 molecules.
DOI: 10.5286/isis.e.rb1520345
title: Specular Reflectivity and Off-specular scattering from artificial magnetic domain patterns

description: The study investigates artificially designed in-plane magnetic domain patterns by polarised neutron reflectometry and off-specular scattering. Stripe domains with in-plane magnetizations are arranged in a head-to-head and tail-to-tail configuration leading to a charged domain wall equivalent to a magnetization component perpendicular to the surface of the thin film. The magnetic stray field landscape arising from these submicron sized magnetic structures has the potential for positioning and transporting magnetic micro- and nano-objects in liquids and therefore provide an excellent platform for various lab-on-a-chip applications. From this experiment we evaluate in which detail qualitative and quantitative information can be obtained from specular and off-specular neutron scattering. The information obtained will provide the basis for tailoring and applications of the magnetic templates.
DOI: 10.5286/isis.e.rb1520350
title: Dynamical Transitions in the Ogg Glasses

description: We request 4 days on IRIS to study the temperature dependance of the structural dynamics in amorphous sodium-ammonia (Na-NH3). This will be the first investigation of the structural dynamics of these phases, and continues our successful studies at ISIS into these intriguing electronic systems. Through the determination of discontinuities in the spatially averaged mean squared displacements of protons, we will be able to identify transition points in the dynamics of our amorphous systems as the temperature is raised
DOI: 10.5286/isis.e.rb1520491
title: Dynamics of amyloid protein fibril elongation using isotope-labelled SANS

description: This proposal combines optical spectroscopy with neutron scattering using novel labelling strategies to investigate ?amyloid? protein fibrils. Variations in packing and in the dynamics of elongation and breakage underpin phenomena ranging from non-genetic heredity in yeast, to diseases such as Alzheimer?s, BSE and CJD. Most solution methods to monitor growth dynamics only give information on the overall % of material transformed from non-fibrillar to fibrillar forms. They cannot determine length distribution or linear growth rates, but instead convolute the two; in other words, they cannot distinguish a few long fibrils each growing quickly, from many short fibrils each growing more slowly. We will determine both fibril lengths and linear growth rates using SANS and insitu optical spectroscopy.
DOI: 10.5286/isis.e.rb1600001
title: Performance evaluation of the IMAT-CCD camera
DOI: 10.5286/isis.e.rb1610365
title: Local structure of the semiconductor caesium lead iodide

description: Caesium lead iodide is of interest both as a photoluminescent material whose optical properties may be tuned by creating nanoscale structures, and as an inorganic analogue of the recently developed solar cell sensitiser methylammonium lead iodide. Rietveld refinement of the high-temperature perovskite phase of this material gives unreasonable atomic displacement parameters on the I atoms, suggesting that the local symmetry of these sites is less than implied by the spatially averaged structure. We propose to collect total scattering data from this material; reverse Monte Carlo refinement will produce a model consistent with the local as well as the average structure. Our results will help to elucidate structure-property relationships in both this specific material and the broader lead halide perovskite family, as well as the development of the RMC technique itself.
DOI: 10.5286/isis.e.rb1610372
title: Molecular and framework dynamics in CH3NH3PbBr3 - a high resolution experiment on IRIS

description: Organic-inorganic perovskites have recently been shown to be potentially efficient and inexpensive photovoltaics.  These materials undergo a series of structural transitions and it is our aim to understand the dynamics driving these transitions.  This proposal requests time to study the dynamics driving the structural transitions in CH3NH3PbBr3 using a combination of high resolution spectroscopy on IRIS, MAPS, and the complementary selection rules of Raman spectroscopy.  This proposal is directed towards IRIS but is paired with a similar proposal on MAPS.
DOI: 10.5286/isis.e.rb1610501
title: Further investigation of unusual inelastic spectrum of Ba2LuMoO6

description: Ba2LuMoO6 is a rare example of an s = ½ undistorted fcc frustrated system, which displays no magnetic order above T = 2 K, and thus is an excellent experimental realisation of a 3D model magnetic system [1]. By analogy with previously reported measurements on Ba2YMoO6 it was expected that we would observe a broad inelastic feature associated with a singlet-triplet excitation. However, very recent measurements on Merlin indicate a large number of different excitations. To verify those results, we request time to investigate these excitations with the higher resolution available on MAPS.
DOI: 10.5286/isis.e.rb1620101
title: Local Structure in PMN Relaxors from Neutron Total-Scattering and X-ray Single-Crystal Diffuse-Scattering Data

description: This experiment seeks to resolve an ambiguity surrounding the structure of a prototypical relaxor ferroelectric Pb(Mg1/3Nb2/3)O3 (PMN).  Relaxors have been studied extensively for nearly 60 years.  Despite all the efforts, the nanoscale structure of these materials remains elusive.  In particular, for PMN, several distinct models have been proposed (e.g., polar nanoregions vs glass-like dipole network) and the debate is ongoing.  We intend to address this problem by exploiting recent advances in structural refinements using multiple types of data.  Local atomic displacements and their correlations will be determined using simultaneous fitting of the neutron total-scattering and X-ray single-crystal diffuse-scattering data in the RMCProfile software.  The goal of the proposed measurements is to provide the neutron total-scattering data for this study.
DOI: 10.5286/isis.e.rb1620144
title: Study of pore-confined CO2 depletion below the bulk triple point

description: Freezing of fluids confined at the nanoscale is of great importance for the understanding of their behaviour due to the confinement effects arising from the finite pore size and the surface forces. Experiments of confined fluids freezing on ordered mesoporous silicas have shown that they crystallise at a temperature below their bulk freezing point depending on the pore size. Surprisingly, our previous neutron measurements carried out at NIMROD showed that CO2 molecules confined in ordered  porous silica (SBA-15), upon cooling below the bulk critical point (T3=216.6 K), neither freeze nor remain liquid, but escape from the pores. This depletion was for the first time observed. We are proposing to further investigate the behaviour of confined CO2 molecules, upon cooling, in silica samples with different pore structure (KIT-6) and pore size (MCM-48).
DOI: 10.5286/isis.e.rb1620440
title: Spontaneous solvation of graphene from KC24(NH3) and KC8 graphite intercalation compounds (GICs) in tetrahydrofuran (THF)

description: Liquid phase exfoliation of graphite is a scalable method for the production of graphene with an inbuilt medium for the manipulation of the graphene into applications. Much like salt dissolving in water, we have recently shown that layered salts of graphite, graphite intercalation compounds (GICs) can dissolve in polar solvents such as tetrahydrofuran (THF). This gentle dissolution results in undamaged, negatively charged graphene sheets in solution.This experiment aims to investigate the mechanism of dissolution of graphite intercalation compounds (GICs), KC24NH3 and KC8 in THF, firstly by monitoring the changes in their structure as the solvent is added, and secondly, by observing the appearance of small angle scattering due to the spontaneous solvation of graphene.
DOI: 10.5286/isis.e.rb1700020
title: Self-assembling behaviour of N-acyl amino acid-based surfactants

description: N-acyl amino acids are surfactants with attractive applications in different technological fields. They are referred to as mild surfactants because they are commonly considered less irritant and safer than sulfates anionic surfactants. N-acyl amino acid surfactants could infact represent an alternative and safer option to SDS. However, the full potential of such surfactants remains unexplored, mainly because of the lack of information regarding a full characterization of their physicochemical and toxicological properties, including their interaction with biological membranes.With the aim to use these compounds as drug delivery agents,we propose here to study their self-assembly behavior in solution. This is uniquely possible by SANS and will help understanding their shape, loading and temperature stability.This study will help us proceeding further in their application in real systems.
DOI: 10.5286/isis.e.rb1500024
title: Crystal quality verification of K0.3MnO3
DOI: 10.5286/isis.e.rb1510049
title: Equations of state of D2O ice III and ice V

description: The high-pressure forms of ice, phases III and V, are the equilibrium solids in contact with liquid water at pressures between 2.5 - 5.5 kbar. Consequently, their properties are important to calculating the volume changes caused by freezing of subsurface oceans inside icy planetary bodies and the buoyancy of icy volcanic melts. To quantify these properties we propose to measure the P-T dependence of the equation of state of ices III and V. Since both have small stability fields, we must quench these phases to &lt; 100 K at high pressure. Furthermore, both phases are inhibited by the use of He pressure media. We propose a unique experiment in which argon is used to synthesize ices III and V, whereafter the system is purged with He so that we can cool &lt; 100 K without freezing the pressure medium. This work will provide accurate equation of state parameters for planetary modelling.
DOI: 10.5286/isis.e.rb1510052
title: Surface structure of ethoxylated PEI/SDS mixtures: optimising surface properties

description: The strong interaction between polyelectrolytes and ionic surfactants can result in pronounced surface adsorption and the formation of surface multilayer structures. This results in important surface properties with potential applications in detergency and in soft lubrication. In this context polyethyleneimine, PEI, based polyelectrolytes are particularly attractive, and  although ethoxylation can fine tune the interactions any enhancement in the adsorption is greatly reduced. We have shown recently (Langmuir 30, 2014, 9761) that the nature of the ethoxylation can be adjusted such that the favourable surface properties are retained. In order to optimise the interaction of the surfactant with the ethoxylated PEI it is now  essential to understand the structure of the surface layer in detail.
DOI: 10.5286/isis.e.rb1510461
title: Binding Particles with Proteins at Interfaces

description: Understanding and controlling the interaction of nanoparticles with biomaterials is key to alleviation of concerns about nanotoxicity. This knowledge can also be used to design ways  to retain defined structures as required for nanofabrication using self-assembled particles. Studies of the simplest model systems are an initial key step. The present proposal is to use neutron reflection and off-specular scattering to observe the organisation of polystyrene latex particles on a protein layer. Moringa oleifera seed protein binds strongly and irreversibly to silica and at macroscopic interfaces such as those on large silicon crystals. The protein also binds to latex particles and these processes are important in understanding water purification using the protein as flocculent. The attractive interaction and binding can also provide a means to lock particles in particular structures.
DOI: 10.5286/isis.e.rb1510529
title: Quantum Methyl Rotors for Gas Sensing in Zeolitic Imidazolate Framework-8

description: We aim to utilise Low-Energy Neutron Scattering (LENS) at OSIRIS to investigate the effects of gas adsorption on the quantum rotation of the methyl groups present in a Metal Organic Framework (MOF) material with zeolitic topology: ZIF-8. We anticipate that the research will lead to the use of tunnelling transitions in the characterisation of gas adsorption and uptake in methyl-containing complex nanoporous media.
DOI: 10.5286/isis.e.rb1510583
title: Studying the Hydration Properties of Green Hybrid Nanocomposite Cellulose Films

description: We are investigating innovative hybrid organic/inorganic multilayered films comprising alternated layers of cellulose nanocrystals (CNCs) and Gibbsite platelets (GW). CNCs are rod like biosourced nanoparticles exhibiting outstanding physical properties that appear as perfect building blocks for the preparation of green or hybrid nanocomposites. The architecture of (CNC/GW) multilayered films was shown to be highly tunable by varying the drying protocol and the salt content. We propose here to investigate by neutron refelctivity the swelling properties of (GW/CNC) multilayers. It indeed appears crucial to check if phenomena like swelling, thickness increase, rearrangement of the nanoparticles, or desorption occur in order to understand the final dry state.
DOI: 10.5286/isis.e.rb1510603
title: In-situ INS study of CO oxidation using Au/FeOx nanoparticulate catalysts

description: The great versatility of Au catalysis has been shown in applications including the selective oxidation of hydrocarbons and alcohols  and the direct formation of hydrogen peroxide. However, most interest has focussed on the oxidation of carbon monoxide (CO) for which supported gold nanoclusters are the catalyst of choice. The Cardiff group have recently developed an iron oxide supported gold catalyst for CO oxidation that, remarkably, is active at room temperature and pressure. Investigations of the catalyst have shown that small quantities of water are essential for its operation, but the mechanism is unclear. The need for water implicates that O¿H groups are involved in the catalysis at some stage. INS spectroscopy on MAPS is readily able to observe O¿H stretch and bend modes. It is proposed to observe the effect of water on the catalyst surface and then to follow CO oxidation in situ.
DOI: 10.5286/isis.e.rb1510629
title: Measuring antioxidant capacity using MuSR

description: Our previous experiment (RB910492) aimed to determine reaction rate constants for muon with Vitamins C and E, thus providing a measure of their relative antioxidant capacities. While we were able to successfully measure the rate of muonium addition to Vitamin C, our attempts to measure the reaction kinetics of Vitamin E were thwarted with difficulties relating to oxygen contamination, systematically introduced in the sample loading procedure. Since this time, there have been significant improvements in the handling of liquid samples and we   now request beamtime to complete the work on Vitamin E. This comprises of a study to investigate the final state species resulting from the reaction of muonium with Vitamin E as well as time to complete our kinetics study.
DOI: 10.5286/isis.e.rb1520001
title: OSTEOMETRICS IN BURNED HUMAN SKELETAL REMAINS: ESTIMATING HEAT-INDUCED DIMENSIONAL CHANGES IN BONES BY NEUTRON SPECTROSCOPY

description: This study aims at developing a reliable method for probing diagenetic alterations in human bones upon burning events, by INS spectroscopy. The results will be coupled to Raman and FTIR data (obtained concomitantly), with a view to better understand heat-induced changes in bone, thus providing a way to estimate their effect on the metric dimensions of human skeletal remains. This is an innovative way of tackling human bone tissue, that will pave the way for the analysis of other types of remains (e.g. teeth), leading to an improved understanding of burning-induced diagenesis. Such a quantitative method for assessing dimensional changes in burned human bones will be of the utmost significance in both anthropological and archaeological contexts, namely for the analysis of burned human remains from forensic scenes (e.g. victim identification) or archaelogical settings.
DOI: 10.5286/isis.e.rb1520154
title: CO2 foams stabilized by W/CO2 interfacially active hydrocarbon surfactants and silica nanoparticles

description: CO2 foams can be formed in water/carbon dioxide (W/CO2) mixtures with the aid of W/CO2 interfacially active hydrocarbon surfactants and surface treated silica nanoparticles (NPs). This proposal examines the nanostructure of CO2 foams; that is, CO2 pockets, aqueous films and adsorbed silica nanoparticulate (NPs) layers at the W/CO2 interface. CO2 foams have attracted much attention as they behave as viscous CO2 fluids and have the possibility to improve the efficiency of enhanced oil recovery (EOR). This SANS study will provide important information needed to advance the theory for designing W/CO2 interfacially active materials for CO2 foam formation.
DOI: 10.5286/isis.e.rb1520264
title: A µSR study of non-centrosymmetric superconductors Re6Ti and Re3Mo

description: Superconductivity in systems which lack inversion symmetry is expected to give rise to a host of unconventional effects, including mixed parity ground-states, and the formation of highly topological surface states.  Our recent focus has been on the detection of time-reversal symmetry breaking in transition metal alloys, as this is one of the clearest signals of unconventional superconductivity.  In this proposal, we suggest an investigation of two members in the family of Rhenium based alloys that crystallize in the non-centrosymmetric alpha-Mn structure.  This will build upon our previous work in this family, and will allow us to build up a picture of how the strength of the spin-orbit coupling affects the parity and pairing symmetry of the superconducting ground state.
DOI: 10.5286/isis.e.rb1520358
title: A Model for Tackifier Elastomer Interaction

description: Oligomers are commonly added to adhesives in order to improve surface tack properties.  However, it is also important that the oligomers do not adversely affect the solid (glassy or crystalline) domains in the elastomer. Subtle changes to the stability of these domains could be responsible for the gradual ageing and loss of mechanical properties of the adhesives.  In order to characterise this and acutely sensitive method is required to measure the interaction between oligomers and materials that are representative of the glassy domains. Here we propose to use neutron reflectivity to analyse swelling and interfacial broadening of fin polystyrene films, which are a one-dimensional analogue of the glassy domains present in adhesives.
DOI: 10.5286/isis.e.rb1520361
title: Time Reversal Symmetry Breaking Non-Centrosymmetric Superconductor LaPtGe and LaIrGe

description: In conventional superconductors gauge symmetry is broken, while in unconventional superconductors other symmetries may also be broken. There has recently been a great deal of interest in noncentrosymmetric superconductors (NCS) due to the complex nature of their superconducting properties. The lack of inversion symmetry in these materials induces an antisymmetric spin-orbit coupling which can lift the degeneracy of the conduction band electrons and may cause the superconducting pair wave function to contain a mixture of singlet-triplet spin states. This mixed pairing can led noncentrosymmetric superconductors to display significantly different properties of that of conventional superconducting systems
DOI: 10.5286/isis.e.rb1520370
title: Residual stress measurements in an aerospace titanium alloy fabricated by additive manufacturing

description: Additive Layer Manufacturing (ALM) is an innovative manufacturing process which offers near-net shape fabrication of complex components. Among the various ALM processes, Selective Laser Melting (SLM) offers high geometrical freedom and a wide material range. However, as a result of the locally concentrated energy input, the temperature gradient mechanism and related plastification leads to significant residual stresses and deformation in the final product. Therefore this study concerns the residual stress measurements in an aerospace component fabricated through SLM from Ti- 6Al-4V powder.
DOI: 10.5286/isis.e.rb1520466
title: Inducing Magnetic Order in Topological Insulators by Ferromagnetic Insulators

description: We intend to study a new class of materials known as 3D topological insulators. The electronic states in these materials  have a non-trivial topology, different to almost all other known materials, and at the interface between these materials and 'ordinary' matter many exotic and novel phenomena manifest themselves. In particular they must have gapless surface states. However, to access much of the new physics of 3D topological insulators it is necessary to open an energy gap in their surface states. The most promising route for this is by inducing magnetic order. We have already studied the effect of doping to induce ferromagnetism in these materials. Here we intend to use polarised neutron reflectometry to spatially resolve the magnetism induced by proximity with a neighbouring ferromagnetic insulator.