cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.5286/isis.e.rb1620453
title: Probing Structural Anomalies in LaCoO3 using Neutron Total Scattering

description: This proposal is concerned with investigating changes in the local structure of LaCoO3 at various temperatures. The arrangement of d-electrons in the transition metal, Co, changes as a function of temperature, going from the so-called 'low-spin' state (which tends to be quite rare in oxide materials) at low temperature to a 'high-spin' state at higher temperatures. These changes must have an effect on the local environment surrounding the Co atoms, i.e. the atomic structure, but any such distortions are not readily seen in the average crystal structure, as determined from standard diffraction experiments. This experiment will use total scattering to probe the local, short-range atomic structure of the material, and provide insight into how the changes in electronic structure manifest.
DOI: 10.5286/isis.e.rb1410451
title: Understanding the Two Step Decomposition of Milled Magnesium Hydride by Neutron Scattering; Part II: In-situ SANS

description: When MgH2 is processed under relatively mild milling conditions it exhibits a two-step thermal decomposition process where loss of hydrogen is associated with each endothermic event. To date, no causal link between the two thermal events and the material has been established and no absolute description of the mechanism involved in the two hydrogen desorption steps has been determined. To unravel the decomposition mechanism of the milled hydride, we propose RT and in-situ small angle scattering measurements to decouple the effects of microstructure and phase behaviour in the dehydrogenation of MgH2; a complementary proposal covering neutron diffraction measurements has been submitted. Here we will determine the particle surface scattering properties of intermediate partially hydrogenated (MgH2-x) phases that evolve during the ¿low temperature¿ (LT) and ¿high temperature¿ (HT) endotherms.
DOI: 10.5286/isis.e.rb1510043
title: Interaction of sugars and a model peptide

description: We propose to perform a NDIS experiments at the SANDALS diffractometer at T = 300 K on 7 aqueous solutions of NMA and trehalose and NMA and glucose,  aimed at investigating the interaction of the two sugars with N-methylacetamide in solution. We have previous evidence of strong differences in the hydration properties of the two sugars, which may have a counterpart in the interaction of sugars with NMA, where NMA is a model system for the amide linkage of peptides and proteins. Investigating the interaction of this small molecule with trehalose and glucose in aqueous solution may address the longstanding question about the highest effectiveness of trehalose as a bio-protectant, compared to glucose. Indeed it is not yet clear if trehalose exploits its action by substituting water in the protein hydration shell,  or not.
DOI: 10.5286/isis.e.rb1510221
title: Detailed Measurements of the Crystalline Electric Field of Shastry-Sutherland Magnets Rare Earth Tetraborides

description: We are proposing to accurately map out the crystal electric field (CEF) levels in NdB4, ErB4 and HoB4 using MARI. These compounds belong to a family, REB4, which is a rare experimental realisation of the Shastry-Sutherland lattice. Despite the CEF interactions having considerable influence on the magnetic properties, very little work has been done to investigate the CEF interactions. We will produce powdered samples of ErB4, NdB4 and HoB4 and have grown single crystals, which we have characterised. These have shown interesting behaviour such as fractional magnetisation plateaux and complex phase diagrams. While neutron experiments we have performed on NdB4 and HoB4 have also shown some intriguing results.
DOI: 10.5286/isis.e.rb1510339
title: Lipid-polymer nanodiscs stabilized with novel sytrene-maleic anhydride derived copolymers

description: Polymer stabilized lipid nanodiscs offer enormous potential as tools for enabling membrane protein structural studies & biophysics. Previously we studied nanodisc formation using a poly(styrene-alt-maleic acid) copolymer, which forms discs above pH 8, and also using a commercially available poly(styrene-alt-maleimide) (PSMI) which forms discs at pH 6. We now wish to study the polymer chemistry in more detail to investigate the effect of structural changes to help determine how the disc structure is stabilized. We have synthesised well-defined precursor poly(styrene-alt-maleic anhydride) and converted this to PSMI with different amine lengths, to alter the size of the hydrophilic part of the polymer, and also made similar polymers using 4-methylstyrene to increase the size of the hydrophobic part. We propose to study the detailed structure of lipid nanodiscs prepared using these polymers.
DOI: 10.5286/isis.e.rb1510399
title: The magnon density of states in NiPS3

description: NiPS3 is an example of a low-dimensional magnetic system.  It is potentially a 'model' magnet, meaning that it might be a good material to search for new phenomena that have been predicted by current theories of magnetism.  This is certainly the case for the related compounds MnPS3 and FePS3 which, despite their similarity in structure, prove to show very different types of model magnetic behaviour.  We now wish to measure the magnetic dynamics of NiPS3 to establish how close it is to being a model magnet, and to compare it to its siblings in the transition metal-PS3 family.
DOI: 10.5286/isis.e.rb1510455
title: Oxidation of thin film at the air-water interface of cloud droplets using REAL atmospheric aerosol from polar, marine and urban sources

description: The Earth's climate is strongly influenced by clouds. The oxidative processing of pollutants in clouds affects droplet size and optical properties, important effects. Common cloud pollutants are naturally occurring organic surfactants forming organic films on the droplet, The climatic effect depends on the rate of atmospheric oxidation of these films and whether any product film forms. In this work we will study the kinetics of hydroxyl radical with insoluble surfactants from samples from Antarctica, mid-Atlantic and Urban London. Specifically we will (a) demonstrate that an aqueous cloud oxidant, the OH radical, can oxidise a real atmospheric organic film with different provenances, b) calculate the effect of the reaction on the hygroscopic properties of a cloud droplet and demonstrate removal of the organic film may cause a cloud to evaporate (c) Support an STFC futures grant.
DOI: 10.5286/isis.e.rb1510605
title: Copy of: ATmospheric Oxidation of MIxed films studied by Neutron Reflectometry and infra-RED reflection absorption spectroscopy (ATOMINRED).

description: Quantifying amount, composition and fate of surface-active organic aerosols originating from cooking processes is a key atmospheric research activity. Our project aims to investigate the oxidation of organic-coated aerosols, particularly for the key night-time oxidant NO3. We carried out experiments on single components and recently moved to more realistic models for cooking aerosols, studying the binary mixtures of the three previously investigated surfactants. We will study the two unsaturated surfactants methyl oleate and oleic acid and three binary mixtures (including saturated stearic acid) exposed to NO3. The newly added method of in-situ infra-red spectroscopy will allow us not only to understand how the interaction between the two components affects the oxidation reaction and its rate coefficient, but also to directly identify reaction products at the air-water interface.
DOI: 10.5286/isis.e.rb1510632
title: Order and disorder in sodium amide

description: Sodium amide has recently attracted interest as a catalyst for the decomposition of ammonia as a means of producing hydrogen. As such, its properties are of increasing relevance to the design and optimisation of sodium amide-based catalyst systems. We have previously observed interesting structural properties in solid sodium amide, including significant disorder in the amide units, even at room temperature. In this proposal, we request two days of access on the SANDALS instrument to measure the diffraction of a sample of sodium amide in order to gain insight into the disorder in the structure as a function of temperature, including the transition from solid to the melt.
DOI: 10.5286/isis.e.rb1620051
title: Nanostructure of a Three-Component Deep Eutectic Solvent

description: Deep eutectic solvents (DESs) are liquids formed from a mixture of salts and molecular species. DESs have remarkable solvent properties and are potentially "greener" alternatives to traditional volatile organic solvents for applications as diverse as electrochemistry and nanomaterial synthesis. The wide range of possible combinations of cations, anions and molecular species allow DES properties to be controlled for a particular application. This work will probe the nanostructure of a DES composed of a 1:1:2 molar ratio of ethylammonium bromide (EABr) to butylammonium bromide (BABr) to urea and compared with the 1:1 molar ratio DESs EABr:urea and BABr:urea to reveal the effect of cation alkyl chain length on nanostructure. Understanding DES nanostructure will aid in establishing structure-property relationships in DESs for facile tuning of properties for future applications.
DOI: 10.5286/isis.e.rb1620087
title: Fire-fighting surfactants: aggregation and micellar composition

description: The aim is to probe micellar structures of three common industrial fluorotelomer surfactants used in fire-fighting foam formulations (Figure 1) using contrast variation SANS. These surfactants will be studied individually, and as mixed systems, using typical compositions found in fire-fighting foam formulations. The data will allow to (1) identify the adopted micelle structures for each surfactant and (2) understand how/if aggregation is affected by mixing. This is the first stage in a new 3-year program, including SANS, so that F-carbon surfactants can be replaced by more environmentally-responsive low-F or hydrocarbon analogues. Chris Hill is a 1st year PhD student fully funded by fire-fighting technology company Angus Fire.
DOI: 10.5286/isis.e.rb1620150
title: The Egyptian grave-goods of Kha and his metals: technology production and corrosion products identification.

description: The proposal aims to a neutron integrated study to provide the composition (in terms of phases and corrosion products as well as working methods and state of conservation) of a set of 5 metallic vassels coming from the Egyptian tomb of Kha and Merit. The study will be performed at ENGIN-X diffractometer through Neutron Diffraction. The proposed experiment is part of a large-range characterization campaign on objects coming from the same Egyptian tomb discovered on February 15, 1906, in a valley next to the village of Deir el-Medina.
DOI: 10.5286/isis.e.rb1620207
title: Dynamics in oleic acid: solid and melt.

description: Increasing interest in biofuels has led to a desire to understand the phase characteristics of the compounds present in these fuels and how the dynamics of the fluid might be affected, especially close to their melting points. The relevance is that a biofuel in extreme low temperatures may undergo a phase change modifying its flow in fuel lines. One of the best biofuels is methyl oleate which has been studied already as part of another project. Intriguingly, this showed anomalous behaviour in the solid form. However, it is not clear whether this was simply a matter of a weak signal or some unexpected change in the material. Clarification of this is required by studying the parent compound oleic acid where we can progressively introduce limited order and hence separate the effects of signal intensity and changes in the material.
DOI: 10.5286/isis.e.rb1620227
title: μSR Study of Non-Centrosymmetric Superconductor La7Rh3 and Y7Pt3
DOI: 10.5286/isis.e.rb1700005
title: Determination of the crystal structure of CsNiCl3 and RbNiCl3 under hydrostatic pressure
DOI: 10.5286/isis.e.rb1700037
title: Beam Testing on ChipIR

description: This is a test of the flux and spectrum on the beam on ChipIR.
DOI: 10.5286/isis.e.rb1410127
title: Alkylammonium Group 14 iodometallates

description: Main group metal iodometallate represent a large class of semiconducting materials which display optical and electronic properties of current great interest in relation to the sensitisation of solar cells for water splitting. Of particular interest are the heavy group 14 iodometalates, since they can adopt perovskitic structures of varying dimensionality and demonstrate large compositional and structural variations.  The orientation of the alkyl groups or water molecules in the structures and role of hydrogen bonding are key aspects that define the type of structure formed and therefore the derived electronic and optical properties. In this experiment we will study several key materials of this type in order to define the positions and orientations of the hydrogen containing sections of the structure ¿ particularly the [- NH3]+ groups - such information only be obtained from NPD data.
DOI: 10.5286/isis.e.rb1510009
title: Growth kinetics of model anti-reflective coatings

description: It is proposed to use time-resolved SANS (TR-SANS) to elucidate growth kinetics of composite latex-silica core-shell particles. These core-shell particles form the basis ofindustrial formulations in anti-reflective coatings, important for optimising efficiencies of solarcells: hence there are environmental, industrial and economic dimensions to this project. Theintention is to use contrast variation to highlight the growth of silica shells aroundmethacrylate-based polymer latex particles. Initial cryoTEM images indicate silicananoparticles (diameter 2-3 nm) form in situ before adsorbing to the latex templates, givingrise to the growth of silica shells. This experiment forms part of a 3 year program seeking toinvestigate the growth kinetics and properties of latex templated silica films, and this is the full kinetic study building on already accepted equilibrium work at ILL.
DOI: 10.5286/isis.e.rb1510037
title: A Total Scattering Study of Aqueous Dopamine Under Conditions of Increased Hydrophobicity and Salinity

description: We request 3 days on SANDALS to study the interactions of the neurotransmitter dopamine hydrochloride in a 1:19 methanol:water mixture and also in an aqueous 3M NaCl solution. This work builds on our previous study of dopamine hydrochloride in aqueous solution in which the conformation of dopamine in solution was assessed together with the hydration of the molecule. The methanol:water solution and aqueous NaCl solution both provide a more complex environment in which to study the conformation and interactions of the dopamine molecule thus simulating aspects of the in vivo environment.  The results will enable further assessment of why dopamine does not cross the blood-brain barrier, while its structurally similar precursor, L-dihydroxyphenylalanine, does.
DOI: 10.5286/isis.e.rb1510189
title: Phase separation in confined block-copolymers on a structured substrate studied by SERGIS

description: Co-polymers confined in small droplets may have a structure different from that in the bulk. These droplets are produced by annealing a spin-coated polymer film with a thickness smaller than the radius of gyration. In principle, the strucure of such a system can ideally be studied by SERGIS. However, earlier experiment showed that the spin-echo signal is too weak to be observed with a reasonable accuracy. Here we propose a method, making use of a strucured substrate, that may enhance the spin-echo signal. A first pilot experiment was promising but inconclusive. Here we propose the investigate this new method in more detail.
DOI: 10.5286/isis.e.rb1510246
title: Understanding Structural Changes in Amorphous Solid Water (ASW) on Heating

description: This experiment will establish the structural changes that occur in Amorphous Solid Water (ASW) prior to the process of pore collapse or crystallisation. We will study the temperature and temporal evolution of this metastable condensed-matter material, particularly in an astrophysical context, looking at how the ice expands and ice surface rearranges. The experiment exploits the unique Q-range capabilities of NIMROD, capable of determining both the micro- and meso-scale structure of samples concurrently.  The results will be of importance in understanding the properties of ASW, the most commonly encountered form of water in the universe, and how the ice expansion at low temperatures impacts on the chemistry and physics that can be occurring during planet and star formation.
DOI: 10.5286/isis.e.rb1510255
title: Nematic spin correlations in the detwined BaFe2-xNixAs2 with in-situ pressure control

description: This experiment brings a new technique to the time of flight neutron scattering. With a device using micrometer to apply displacement on multiple springs, we can now make in-situ pressure control in uniaxial pressure detwining experiment. This proposal aims to investigate the nematic phase in iron based superconductors and its evolution with respect to temperature and pressure change.
DOI: 10.5286/isis.e.rb1510563
title: Characterization at low Q values of a thermo and pH-sensitive hydrogel

description: Among soft colloidal systems microgels, aqueous dispersions of nanometer or micrometer-seized hydrogel particles, have been the subject of intense research in the last years because of their versatility and high sensitivity to external stimuli. In particular the responsive hydrogel we are investigating is composed of Interpenetrated Polymer Network (IPN) of poly(N-isopropylacrylamide) (PNIPAM), a thermo-sensitive polymer, and polyacrylic acid (AAc), a pH-sensitive polymer, dispersed in water. The existence of a thermoreversible transition corresponding to the swollen-shrunken volume phase transition due to the presence of PNIPAM has been highlighted. Adding PAAc introduces an additional pH-sensitivity with respect to the temperature-sensitivity and leads to interesting differences in the transition process at acidic and neutral pH which need to be accurately investigated.
DOI: 10.5286/isis.e.rb1510594
title: A PDF investigation of synthetic Georgite - a new, high activity catalyst

description: Synthetic Georgite has shown high catalytic activity for a number of catalytic processes including methanol synthesis and the water gas shift reaction. Consequently, it is of considerably interest to the catalysis community. However, characterization of this material is notoriously difficult due to its highly amorphous nature. Preliminary X-ray PDF and IR spectroscopy has identified some of the species present and their relationships but currently there is no information on the hydroxide and carbonate interactions with the metal species. We wish to perform a neutron PDF experiment to fully characterize determine these interactions to develop our understanding of this materials and also as a fore-runner to future experiments where these features will be investigated as a function of temperature.
DOI: 10.5286/isis.e.rb1510628
title: Kinetics of Hydrogen Abstraction in Alkanes by Mu Reactivity studied by RF Resonance

description: Hydrogen abstraction reactions are key steps in free radical mechanisms that dominate the combustion and atmospheric chemistry of the alkane hydrocarbons and, as such, merit study for their relevance to current environmental concerns. The lower mass alkanes also provide important test cases for H-atom reaction rate theory for polyatomic systems. Due to its remarkably light muon mass, studies of Mu reactivity provide unique tests of quantum mass effects in rate theory. RF techniques provide a unique method for studying slow reaction rates, and have been applied to measure an average rate constant for propane at 300K. Results suggest a dominant contribution to the Mu reaction from quantum tunnelling, and it is this we want to investigate in this new proposal through variable temperature measurments on both propane and butane.
DOI: 10.5286/isis.e.rb1610185
title: Anomalous fast diffusion of Cu ions in superionic and liquid phases of CuI

description: CuI is well-known to exhibit the superionic behaviour in the high temperature solid state (α-phase), where the mobile Cu ions migrate among the interstices in the f.c.c. sublattice formed by immobile I ions. Even in molten state, Cu ions has 8 times faster diffusion constant than I ions. Such asymmetric behavior between cations and anions can be caused by polarization of anions. From QENS, we distinguished three dynamical modes exist in molten phase, which are slowest diffusion of I ions, intermediate mode of Cu diffusion and fastest local dynamic mode like a rattling vibration. Deep inelastic neutron scattering by VESUVIO can allow us access directly kinetic energy of each constituent. By comparing non-superionic, superionic and liquid phases, the origin of existence of superionic phase regarded as partial melting or partial solidification can be revealed.
DOI: 10.5286/isis.e.rb1620071
title: Combined SAXS and SANS analysis of strained composite materials

description: The microscopic origins of strain softening (Payne Effect) are vital to our understanding of energy dissipation in vehicle tyres.  This proposal builds on our recent SANS experiments in which we have identified the structure of a model silica in polybutadiene nanocomposite and the relationship to rheological behaviour.  We have also quantified the extent of a glassy layer of polybutadiene at the silica interface.  Here we propose to combine SANS and SAXS on cross-linked nanocomposites under strain, which will uniquely be able to identify the extent of polymer and silica network deformation respectively.  SANS will use contrast labelled PB/dPB to detect chain stretching while SAXS will use the inherent contrast between the silica and the polymer to quantify deformation to the silica network.  In each case 2d detectors will enable the anisotropy of the strained components to be resolved.
DOI: 10.5286/isis.e.rb1620143
title: Aggregation of new silicon containing surfactants (NOT silicone surfactants)

description: The results from this experiment will develop alternatives to controlling surface tension through the design of 21st century surfactants (better performance at lower concentration with lower environmental consequences) by gaining essential information on how molecular structure affects aggregation. A sister proposal has been submitted this round to study adsorption of this new series of surfactants by neutron reflectivity ("Adsorption of new silicon containing surfactants (NOT silicone surfactants)")
DOI: 10.5286/isis.e.rb1620170
title: Structural Studies of Umbite-related Ion Exchange Materials

description: The aim of this research is to determine structural systematics of a series of materials with compositions and structures related to the mineral umbite (K2ZrSi3O9·H2O) and some of their products after ion exchange with Sr2+ or Cs+. This work is part of an EPSRC funded proposal to produce and test new materials for removing radioactive Sr and Cs from effluent during future decommissioning and decontamination activities of the UKs legacy nuclear waste. The information on the parent umbite materials and those showing high levels of ion exchange will be correlated to the ion exchange efficacy and with complementary atomistic modelling studies be used to understand how structural changes are linked to ion exchange.
DOI: 10.5286/isis.e.rb1620176
title: Are Ca2LaFe2SbO9, SrLa2FeNiSbO9 and CaLa2FeCoSbO9 relaxor ferromagnets?

description: La3Ni2SbO9 exhibits relaxor ferromagnetic behaviour in an analogous way to relaxor ferroelectrics. To investigate whether relaxor ferromagnetic behaviour can also occur in iron-containing compounds we synthesised novel Ca2LaFe2SbO9, SrLa2FeNiSbO9 and CaLa2FeCoSbO9. Magnetometry measurements are very promising with Ca2LaFe2SbO9, SrLa2FeNiSbO9 and CaLa2FeCoSbO9 having Curie temperatures of around 280 K, 280 K and 270 K. We request a day on GEM to collect data on all three compounds at room temperature and at 5 K to determine their crystal and magnetic structures.