cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.5286/isis.e.rb1610028
title: Unlocking the Lyotropic Liquid Crystal Phases of Novel Photosurfactants

description: Photosurfactants (PS) demonstrate the combined ability to change their shape upon irradiation with light and self-organise into polymolecular assemblies. However, the phase behavior of PS is not well-established and there have been limited reports of their lyotropic liquid crystal (LLC) phase formation. Here, we will undertake a strategic structure-activity study to identify the key structural features required to unlock the LLC phases of azobenzene PS. Small-angle neutron scattering (SANS) will allow us to directly observe the size and shape of PS aggregates as a function of increasing concentration, and thus observe how they grow and begin to assemble into LLC phases. The objectives of this study include to: (i) determine the effect of photoswitching on the polymolecular structures formed; (ii) track the self-assembly and growth of PS aggregates from isolated micelles to LLC phases.
DOI: 10.5286/isis.e.rb1610054
title: Novel state of matter in the site-ordered double perovskites Ba2YWO6

description: In solids, spins and orbitals are usually not coupled to each other. This may be not true any more in the rocksalt ordered double perovskites having spin-orbit coupling. Possibly, spin-orbital entangled liquid may be realized in this class of materials. We explore this possibility in Ba2YWO6 (Fm‐3m) with localized W5+ (5d1) electrons. By measuring low-energy excitations using inelastic neutron scattering, we prove/disprove the emergence of entangled liquid-like state of matter.
DOI: 10.5286/isis.e.rb1610217
title: Investigating proton motion in battery and hydrogen storage materials

description: Our research team have an ongoing project investigating ion diffusion processes in solid electrolyte and hydrogen storage materials. In terms of the former, we have been investigating the development of new electrolytes for solid state Lithium ion batteries. In these systems it has also been shown that ready exchange of Lithium ions for protons can occur, with the exchanged materials showing comparable ionic conduction, thus indicating significant proton conduction. In terms of our work on hydrogen storage materials, we have been investigating the correlation between ion conduction and the temperatures at which dehydrogenation/rehydrogenation will occur. The aim of this experiment is to use quasielastic neutron scattering to gather detailed information on the conduction of protons in these systems, with a view to improving our understanding of these complex systems.
DOI: 10.5286/isis.e.rb1610295
title: In-situ neutron diffraction and conductivity measurement for high proton conducting Sr1-xBaxCe0.5Zr0.35Y0.1Sm0.05O3

description: Sr1-xBaxCe0.5Zr0.35Y0.1Sm0.05O3-&; (SrBCZYSm) where x = 0,0 - 0.9 are promising as intermediate temperature solid oxide fuel cell electrolyte. PXRD reveals that all of the samples show cubic symmetry. Impedance studies confirm that the conductivity is dominated by protons at intermediate temperature and increases with increasing the proportion of Ba in the structure. Fuel cell test observed peak power densities of 695 mW/cm2 at 600 °C, which is highest performance until now for x=0.9.This proposal requests 4 days beamtime on Polaris to perform an in-situ experiment studying ionic (proton) conductivity during the diffraction experiments as a function of temperature on SrBCZYSm in dry and humid atmosphere. The outcome of this in-situ experiment will provide us a deeper understanding of the structure-property relationships within these types of proton conducting samples.
DOI: 10.5286/isis.e.rb1610320
title: Magnetic excitations in the new S = 1/2 kagome antiferromagnet and quantum spin liquid candidate ND3+2xCu3-xMo2O8(OD)2

description: Materials which display exotic electronic states are of great interest to fundamental science, such as quantum spin-liquids (QSL) which are theorised to underpin the transition to high-Tc superconductivity. Inelastic neutron scattering has recently revealed fractionalised excitations in the S=1/2 kagome magnet herbertsmithite, a hallmark of a QSL state. Such a highly frustrated state survives in this material despite cationic disorder which perturbs the 2-D magnetic structure. Here we propose to measure a material with remarkably similar properties, ND3+2xCu3-xMo2O8(OD)2, where the kagome lattice is slightly depleted. Bulk magnetisation measurements reveal strong antiferromagnetic interactions (~300K) yet no sign of long-range magnetic order down to T = 2K. Therefore, this material offers the potential to explore QSL states as well as provide an interesting comparison to herbertsmithite.
DOI: 10.5286/isis.e.rb1610433
title: Study of self-organization of cationic pH- and thermo responsive copolymers with gradient composition in water

description: The aim of our work is to study structural properties of supra-molecular assemblies formed in aqueous solutions of cationic pH- and thermo-sensitive block-gradient copolymers comprising one block of poly(dimethylaminoethyl acrylate) (DMAEA) and one or two terminal blocks with a gradient sequence of styrene (S) and DMAEA monomer units. We expect that because of the gradient sequence of the terminal blocks such copolymers are capable of reversible association giving rise to micellar-like aggregates in aqueous solutions as a function of both pH and temperature. The cationic charge of the PDMAEA blocks opens the perspective to use this smart copolymer nanostructures as non-viral vectors for genetic material.
DOI: 10.5286/isis.e.rb1610482
title: Protein-Ionic liquid interactions: A window into future sustainable processing of proteinacious biopolymer waste and generation of novel com

description: Processing of complex biopolymers, particularly proteins such as keratin and silk, has been hindered by the extremely low solubility and thus accessibility to the protein backbone of these materials.  Recent work shows that room temperature ionic liquids (RTILs  liquids composed of organic-based ions) are able to overcome these issues, rendering them accessible to further processing.  This opens up a wide possible range of applications for turning these materials into novel structures and composites.  This proposal seeks to understand the basis of protein-ionic liquid interactions such as to make more informed decisions of which of the millions of available RTILs to use, ensuring that sustainable and environmentally compatible selections can be rationally prioritised in the future.
DOI: 10.5286/isis.e.rb1610498
title: Effect of electron and hole doping on the spin gap formation in Kondo insulator CeFe2Al10

description: CeFe2Al10 belongs to the CeT2Al10 family (T: Ru, Os, Fe), which exhibits Kondo-insulator properties, with an unusual competition of strongly anisotropic crystal-field and exchange interactions, as well as c-f hybridization. The spin gap has been investigated in these parent compounds using inelastic neutron and exhibits strong anisotropic behavior. Further the effect of electron doping shows dramatic effect in the spin gap of T=Ru and Os, but hole doping does not affect the spin gap very much. Recently the magnetic and transport properties of electron and hole doped CeFe2Al10 have been investigated, which show very dramatic changes. We therefore propose here to study the evolution of its spin-gap magnetic response as a function of electron or hole doping in CeFe2Al10 using MERLIN.
DOI: 10.5286/isis.e.rb1620013
title: Investigation of phonon anomalies in the CDW phases of 1T-TaS2

description: 1T-TaS2, an archetypal quasi-2D compound, reveals strong electron-phonon (e-p) coupling responsible for charge-density-wave (CDW) instabilities leading to a series of phase transitions: from unmodulated structure into incommensurate CDW phase;then to nearly commensurate and finally to commensurate CDW state.Ta4+ ions adopt David star pattern,where 5d electrons on 12 of 13 ions form molecular orbitals leaving center ion with free S=1/2 spin.Despite huge interest in CDW phases,little is known about e-p coupling in TaS2.To our best knowledge no inelastic neutron experiment has yet been done on TaS2 which would otherwise reveal which particular phonon modes are involved at CDW transitions.We propose to investigate the temperature evolution of phonon density of states in 3 CDW phases by inelastic scattering using MARI with the aim of improving our understanding of e-p mechanism in CDW phases.
DOI: 10.5286/isis.e.rb1620097
title: Study of Deep Eutectic Solvents dilutions: nanometer size domains and molecular re-organization

description: Carbon materials with nanopore structures are of great importance for development of energy storage and gas adsorption devices. The critical parameter is pore size and it is difficult to predict. Our group is focused on preparing such carbons from solvents that contains a carbon precursor and does not contain water, the so called deep eutectic solvents (DES). DES are mixed with a water solution of formaldehyde to form a polymer that after carbonization generates the porous carbon. We have hypothesized that pores come from the formation of DES-water nanodomains when the DES is mixed with the water solution. H NMR and Brillouin spectroscopy of water-DES mixtures and simulations seem to agree with the hypothesis. Just by using neutron diffraction to analyse the mixtures would be possible to address this really interesting issue that could allow us to easily predict pore sizes of carbons.
DOI: 10.5286/isis.e.rb1620264
title: µSR investigation of NaxLi12-xC60

description: An economy based on hydrogen as an energy carrier is one of the most promising solutions against the greenhouse effect problem, due to the large amount of energy produced by the reaction of H2 with O2 and the clean combustion, free from pollutants. In the wide panorama of hydrogen storage materials, carbon based nanostructures are rather attractive, thanks to the low weight and cost of carbon. In particular, the alkali cluster intercalated fullerides guarantee hydrogen storage performances, partly meeting the US Department of Energy (DOE) requirements for on-board applications.With this proposal, we seek to further investigate the mechanisms behind the absorption of hydrogen, exploiting the unique capability of µSR technique to study separately the atomic hydrogen chemisorption through the formation and the further reaction on muonium (Mu), a light isotope of hydrogen.
DOI: 10.5286/isis.e.rb1620464
title: Magnetic and lattice excitations in multiferroic BiMn2O5

description: The exchange-striction mechanism, where parallel or antiparallel alignment of an ion's spin with its neighbour leads to displacements away from or towards the neighbour which can add up to a net electric polarisation if the ions carry different charges, is thought to be the underlying mechanism behind the magnetically induced ferroelectricity in BiMn2O5 and other RMn2O5 (R=rare earth, Y, Bi). In BiMn2O5 in particular, a high field spin-flop transition was found to be accompanied by a flip of the electric polarisation, illustrating their close affinity. This proposal seeks to measure the magnon spectrum in a powder sample as a first step to determining the spin Hamiltonian governing the magnetic behaviour, including the spin-flop transition, and also to determine the changes in the lattice dynamics with the magnetoelectric ordering.
DOI: 10.5286/isis.e.rb1670561
title: Nuclear Transmutation of LLFP nuclei by muon nuclear capture reaction

description: Negative muon is 207 times as heavy as electron, and behaves as a heavy electron in materials. Muon is caught by a nucleus (atomic number Z) to form a muonic atom to be captured by the nucleus. The muon is combined with a proton in the nucleus to convert to a neutron and a neutrino. This process is called "muon nuclear capture reaction", and produces nuclear isotopes with Z-1. The process is considered as one of promising reactions to make nuclear transmutation of long-lived fission products (LLFP) nuclei like 107-Pd contained in spent nuclear fuel. The development of nuclear transmutation to stable and/or short-lived nuclei is an urgent social issue. The proposed research aims at understanding a mechanism of muon nuclear capture reaction with isotope-enriched Pd targets by observing associated gamma-rays, and exploring the reaction path and efficiency toward nuclear transmutation.
DOI: 10.5286/isis.e.rb1700033
title: The solvation of ammonia borane by diglyme

description: Ammonia borane (AB) is arguably the most promising hydrogen storage material for use in clean, green fuel applications. Simple heating of AB produces hydrogen that can be used to generate electricity with a fuel cell, the only byproduct being water. The hydrogen release properties of AB can be improved by the addition of a polyether. Studying the interactions between AB and the polyether could provide insight into what causes the improvement as well as potentially let us suggest additives that further improve the system. Diglyme is a solvent which structurally resembles a shortened polyether chain, and should interact with AB in the same way. By observing the solvation of AB in diglyme with neutron scattering, we will obtain structural information on the AB-polyether system that we cannot get from other techniques like X-ray scattering; which do not show much information on hydrogen.
DOI: 10.5286/isis.e.rb1710270
title: Strain Relaxation Measurement combined with High-cycle Fatigue of Nano-crystalline Metals at Cryogenic Temperature

description: The term nano-crystalline refers to a group of metals, abbreviated as NC metals, with typical grain sizes of a few hundred nanometres. An increase in static strength of NC metals allows one to expect an increase in fatigue strength as well. Most of the improved mechanical properties observed in NC metals are attributed to the reduction in grain size; improvements that can be lost if the nano-grains evolves away from the NC state. Fatigue failure due to repetitive loading of metals is a pervasive engineering concern. Unfortunately studies into the fatigue mechanisms are very limited. The aim of this work is to develop a better understanding of fatigue-induced grain growth in NC metals. The nanostructured titanium alloys are due to be used to manufacture high-strength fasteners in the aerospace sector. Thus the research will contribute to their fatigue lifetime prediction.
DOI: 10.5286/isis.e.rb1720260
title: Entropy meets enthalpy: accessing vibrational entropy in flexible metal-organic frameworks by using neutron inelastic scattering

description: Flexible metal-organic frameworks (MOFs) such as [Al(bdc)(OH)] (MIL-53) and Zn(C3H3N2) (ZIF-4) have attracted a great deal of attention recently due to their fascinating non-porous to porous phase transition upon the application of external stimuli such as temperature, hydrostatic pressure or gas pressure. Despite the large interest in these materials, lattice dynamic studies focusing on the origin of these phase transitions are rare. In a simple picture, there exists a balance in flexible MOFs between enthalpic effects (dispersion interactions) in the dense modification and entropic contributions (vibrational entropy) in the porous phase, which can be accessed by the external stimulus. To quantify the role of vibrational entropy and access the detailed origin of the phase transition, we here propose an inelastic neutron scattering study on a series of different flexible MOFs.
DOI: 10.5286/isis.e.rb1720501
title: Characterisation of the anhysteretic superelastic behaviour of Ni-Fe(Co)-Ga magnetic shape memory upon load/unload at varying temperature.

description: Magnetic shape memory alloys are a unique class of material which produce huge elongation (up to 6%) upon the application of a magnetic field. This combined with fast response and long fatigue life makes them ideal for actuator applications . We will be studying the underlying mechanism of a martensite transformation which is responsible for these effects. This proposal will shed light on the fundamental aspects of this transformation.
DOI: 10.5286/isis.e.rb1761006
title: In vivo study of phase transformation in superelastic orthodontic archwires during intraoral exposure

description: The success of an orthodontic treatment highly depends on appropriate archwire selection as well as a clinician's ability to predict response during treatment. Precise knowledge of the appliance properties is thus essential. When it comes to simulating the complex oral environment, in vitro methodologies cannot adequately model in vivo phenomena. Reusing archwires is common practise, although the detailed information of the influence of intraoral service on the materials still lacks. We are looking to fill this void by conducting in vivo retrieval analyses of phase transformation in superelastic orthodontic archwires during intraoral exposure using neutron spectroscopy. Retrieved and as-received nitinol archwires will be measured to determine the phase and texture change induced, relating this to mechanical property change, in order to inform practical treatment protocal adjustment.
DOI: 10.5286/isis.e.rb1768037
title: Characterising Early Iron Age Indian Iron Smelting Technology

description: Recent archaeological research, supported by radiocarbon dates, indicates that iron production in India can now be dated to the earlier part of the 2nd millennium BC, pre-dating the Bronze-Iron transition in Anatolia and the Eastern Mediterranean. Conventional bulk chemical analysis of silicates (e.g smelting slag, ore, furnace lining) and metal artefacts is destructive. We will use neutron and muon instruments at ISIS to obtain genuine bulk compositions, without dissolving or crushing-up samples, or cutting metallographic sections from the irreplaceable archaeological material. We propose to use negative muon analysis to do non-destructive bulk chemical analysis of the earliest-dated smelting slag, furnace lining, and ore fragments from archaeological sites in Uttar Pradesh and Madhya Pradesh, India. We request 9 days of muon beamtime, and 5 days of INES beamtime, to carry out the work.
DOI: 10.5286/isis.e.rb1410529
title: Uptake of pristine C60 into micelles formed by an alkyl-C60 hydrophobic amphiphile

description: The ability of micelles of C60-containing hydrophobic amphiphiles to incorporate pristine C60 will be explored. Contrast variation SANS (CV-SANS) will be employed to fully characterise the structure of these complex fluids. This will answer a fundamental question regarding the extent to which hydrophobic amphiphiles possess properties similar to their classical counterparts: Classical surfactants can typically stabilise dispersions of two immiscible species (e.g. water in oil); hydrophobic amphiphiles have yet to be demonstrated to do so. SANS beam-time is therefore requested as the only viable way to reliably detect the nanoscale structures. The obtained results will greatly increase our understanding of alkyl-aromatic hydrophobic amphiphilicity. The use of ternary phases will also provide further means of control over the self-assembled structures.
DOI: 10.5286/isis.e.rb1510040
title: Studies of Diffusion of Adsorbed Gas Molecules in a Porous MOF by QENS

description: We request 6 days on IRIS to study the diffusion of adsorbed gas molecules (H2, CH4, C2H2, C2H4, C2H6) within a functional porous metal-organic framework (MOF) as a function of gas loading and temperature. The proposed study will reveal the nature of the diffusion of the gas molecules; that is of particular interest owing to the selective hydrocarbon uptakes exhibited by this MOF. Furthermore the data obtained from the QENS study will enable the activation energy of the diffusion to be quantified and the geometry of the binding sites to be determined. These studies on the kinetic aspect of the gas adsorption have significant impact on the practical application of this MOF material for hydrocarbon separation.
DOI: 10.5286/isis.e.rb1510095
title: Simultaneous Raman and INS studies of ethanol isotopomers

description: Ethanol is a compound that is ubiquitous: it is the key ingredient in alcoholic drinks, it is used in low temperature fuel cells and has even been observed in interstellar clouds. Consequently, the spectroscopy has been extensively studied. Unsurprisingly, most of the work has focussed on its properties in solution or the liquid phase and in the gas phase, while the solid state has been largely neglected. The solid state of ethanol is of interest because it readily forms a glass which can be progressively transformed to an orientationally disordered cubic phase and then to a monoclinic crystal. The aim of this proposal is to record high resolution INS spectra across the 0 ¿ 2000 cm-1 range with TOSCA of C2H5OH, C2D5OH and C2D5OD in all three phases. (C2H5OD has already been done using Xpress). Simultaneously recorded Raman spectra will be used to monitor the phase.
DOI: 10.5286/isis.e.rb1510168
title: Corona Dynamics in Polymer Stabilised Nanocomposites

description: The Payne effect, whereby filled polymers experience a loss of modulus under applied strain is responsible for much of the energy loss of vehicle tyres in everyday use.  It has been postulated that this is due to a layer of glassy polymer on the particle surface, arising from the well-known anomalous glass transition, which span the network.  Others object to this theory and instead suggest that chain ends in the vicinity of nanoparticles are responsible for this effect.  Here we have devised an experiment to highlight the dynamics of polymer chains in the vicinity of nanoparticle surfaces using isotopic labelling and QENS.  Samples in which an adsorbed layer of hydrogenous polymer forms the corona of the nanoparticles (of thickness determined by the molecular weight) will be studied over a range of temperature so that the influence of nanoparticle surface on dynamics can be isolated.
DOI: 10.5286/isis.e.rb1510208
title: Auger recombination in low temperature silicon measured by photo-MuSR technique

description: We measure electron-hole recombination rate in low-temperature pure silicon using the photo-MuSR technique. The previous works have measured the recombination rate down to -30 C, and there is no experiment below this temperature. The low T experiments are important not only for the industrial applications but also for the semiconductor physics. In low-T pure silicon the Auger recombination becomes the predominant process. Little is known about how the Auger recombination depends on the temperature in the low-T regime. We have recently observed the photoinduced electrons in Si depolarising the muon asymmetry, which is described by the cyclic charge exchange process. Therefore the muon spin relaxation rate can be utilised to measure the photoinduced electron density. By making a delay between the muon and light pulse we can observe its dynamics.
DOI: 10.5286/isis.e.rb1510226
title: Dynamics of Phospholipid Based Vesicles: Effect of Addition of Salicylate Drugs and Amyloid Beta Peptides

description: Structure and functions of cell membrane are susceptible to alterations as a consequence of interactions with chemical species. The objective of the proposed experiment is to study the effect of addition of salicylate drugs and amyloid beta (ABeta) peptide on the dynamics of phospholipid based uni-lamellar vesicles using quasi-elastic neutron scattering study. ABeta peptide plays a critical role in proliferation of Alzheimer¿s disease and salicylate drugs are the main ingredients in aspirin that is used widely in medications as an analgesic to relieve pain and reduce fever. This user proposal will help us to understand the interaction of these additives with lipid bilayer and its correlation with the microstructure of the vesicles.