cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.5286/isis.e.rb1620161
title: Magnetic ground states in correlated alkali-metal triphenylides

description: Polycyclic aromatic hydrocarbons have emerged as an exciting class of materials with the report of  superconductivity in alkali doped picene with Tc=18 K. However, due to poor crystallinity and multiphase samples the confirmation of the putative superconducting phase has been problematical. We recently devised an alternative synthetic route to making such systems using reduction chemistry of polycyclic aromatic hydrocarbons which has resulted in the synthesis of a new family of tuneable magnetic organic materials, the triphenylides  M2(C18H12)2(DME), where M=K,Rb,Cs and DME=1,2-dimethoxyethane. Although these are not superconductors, they do show intriguing magnetic properties with unusually large exchange couplings. Crucially their ground states are currently unknown and here we propose a muSR study of this system with the aim of elucidating its low temperature magnetic properties
DOI: 10.5286/isis.e.rb1620263
title: Origin of Anomalous Thermal Expansion in Ih phase of Protonated (H2O) and Deuterated (D2O) ice

description: Among the all known crystalline ice phases, ice (Ih phase) exhibits anomalous thermal expansion behavior. We propose to measure phonon density of state of protonated ice (H2O) and deuterated ice (D2O) in Ih phase at 240 K at different pressures up to 1.8 kbar. The measurements will enable to determination of the energy dependence of the Grüneisen parameters strictly in Ih phase thereby quantitative calculation of the thermal expansion coefficient from phonon data to be undertaken. Apart  from  the  pressure  studies,  we  would  also like  to  measure  the  temperature dependence of   phonon frequencies  in the Ih phase of  both the protonated (H2O) and deuterated ice (D2O). The combination of temperature and pressure measurements would help to determine the implicit as well as explicit anharmonicities. We also plan to do  ab-initio calculations for analysis of the experimental data.
DOI: 10.5286/isis.e.rb1620311
title: Solubilisation Dynamics in Microemulsion Systems

description: The dynamic aspects of solubilisation of oils into surfactant systems, often forming microemulsions, are only little known so far, despite their importance for optimising systems with respect to solubilising and releasing hydrophobic compounds. This question will be addressed by using mixtures of deuterated and protiated oils. We will address the question of oil exchange between microemulsion droplets as well as oil incorporation into micellar systems. Here we will look at effects of electrostatic repulsion, the presence of cosurfactants and also look at different surfactant types, with a focus on a system with a particularly stable surfactant monolayer. From these experiments we expect to gain substantial new insights into the basic mechanisms that control the transport of hydrophobes in surfactant systems and thereby contribute to the development of delivery and uptake systems.
DOI: 10.5286/isis.e.rb1670575
title: muSR study of the Cu-spin correlation in the optimally and over reduced T'-Pr1.3-xLa0.7CexCuO4+d (x=0.05, 0.10) single crystals

description: The aim of the proposed study is to obtain detailed information on the Cu-spin correlation in optimally and over reduced single crystals of the electron-doped high-Tc T'-cuprate Pr1.3-xLa0.7CexCuO4+d (PLCCO) with x=0.05, 0.10 from muSR measurements.  Recently, by the improved reduction annealing, we have succeeded in obtaining superconducting single crystals of the underdoped PLCCO in which the ground state was believed to be antiferromagnetic.  From the temperature and x dependences of the muSR spectra, significant information on the Cu-spin correlation and its relation to the superconductivity in the optimally and over reduced T'-cuprates in the underdoped regime would be provided.  In combination with the transport results and our proposed band picture, this study would lead to the whole understanding of the physics of the superconductivity in the T'-cuprate
DOI: 10.5286/isis.e.rb1710247
title: The role of chirality on polymeric membrane lytic activity

description: The human body has a well developed membrane chemistry which allows transport of fluids and salts whilst preventing other molecules and harmful agents from penetrating the cell. Transport of drugs and other benefit agents relies on developing agents which behave like the constituents of the cell membrane but then release their payload on entering the cell. The aim of this proposal is to establish how modifying the chemistry of a copolymer which forms tubes at a high pH can be manipulated to give the appropriate degree of pH response in order to ultimately develop a suitable delivery system.
DOI: 10.5286/isis.e.rb1720061
title: The effect of electron-phonon coupling on the nuclear dynamics of MgB2

description: We propose a spectroscopic experiment to characterise the effect of electron-phonon coupling on the nuclear dynamics of Mg and B in the the MgB2 superconductor. The superconducting temperature of this layered material is anomalously high. An explanation to this feature has been proposed, based on a strong electron-phonon coupling constant connecting the chemical bonds in the B layer and the stretching nuclear vibrations in the same plane. This scenario suggests that the B and Mg nuclear dynamics are differently affected by the onset of the superconducting transition, and that the key to the interpretation of the properties of MgB2 lies in the anharmonicity and anisotropy of the atom local potential. Therefore, we request beam-time on the VESUVIO spectrometer to measure the momentum distributions of B and Mg and infer the shape of their local potential.
DOI: 10.5286/isis.e.rb1720237
title: Study of the reorganization of DES upon dilution with Benzylalcohol

description: Nanoporous carbons 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). Normally, DES are mixed with water to generate pores however, sometimes water cannot be used in the preparation of materials. In previous experiments we hypothesized that pores come from the formation of DES-solvent nanodomains. Some techniques like H NMR and Brillouin spectroscopy reveals that DES-solvent domains  change their tendency at different dilutions depending on the solvent. In this experiment we want to analyse DESs diluted with benzyl alcohol using neutron diffraction to understand the differences found  when mixing a DES  with BA or W.
DOI: 10.5286/isis.e.rb1720285
title: Structural behaviour of gallium in phosphate glasses for bone cements

description: Bone cements are an important class of biomaterial used in hard tissue surgery as well as periodontology. Many of these are glass-ionomer cements formed from an aluminosilicate glass and a polyacrylic acid. There has been some concern regarding the neurotoxicity of aluminium ions in vivo and research is now focussed on alternative materials for the glass component. Gallium phosphate based glasses represent one such alternative. Not only does gallium act in a similar way to aluminium in phosphate glasses, it is also known to show antibacterial properties. The present study is aimed at establishing the structural role of gallium in candidate glasses for bone cements using reverse Monte Carlo Analysis of diffuse neutron scattering data. These results will be used to give an overall picture of the glass structure and the ability of Ga3+ ions to participate in cement formation.
DOI: 10.5286/isis.e.rb1720424
title: Organization of mitochondrial membranes upon oxidative stress: Impact on apoptosis regulating protein-lipid interactions of Bcl-2 proteins

description: Mitochondria are not only the powerhouse of the cell, but are also involved in cellular suicide via apoptosis (programmed cell death). The mitochondrial apoptotic pathway is a major regulator in mammalian cells death, where pro- and anti-survival Bcl-2 proteins meet at the mitochondrial outer membrane and tightly regulate the fate of a cell. Treatment-resistant tumour cells often possess mitochondria which are enriched in the pro-survival Bcl-2 membrane protein which blocks any apoptotic signals upon onset via oxidative stress. Our main aim is to generate by using neutron reflectometry fundamental knowledge about the membrane mediated function of the cell-death causing (anti-survival) Bax protein and its counterplayer, the pro-survival  Bcl-2 membrane protein to regulate and execute apoptosis; information also useful for novel cancer strategies.
DOI: 10.5286/isis.e.rb1720436
title: Atomic structure of formamidinium lead iodide perovskite

description: New perovskite phases containing lead and halogens with a molecular cation are providing new options for materials in solar cells, giving unusually high efficiencies in converting light to electricity. The high-temperature phases of these materials have orientational disorder of the molecular cations. Here we propose an experiment on the new material formamidinium lead iodide, for which disorder in the high-temperature cubic phase has been identified. Our proposal is to perform total scattering measurements from which we can extract the pair distribution function (histogram of interatomic distances), and to analyse the distribution of molecular orientations using the Reverse Monte Carlo method.
DOI: 10.5286/isis.e.rb1770010
title: Broken time reversal symmetry in the superconducting state in Lu5M6Sn18 (M = Co, Rh, and Ir) probed by µSR

description: High quality single crystals Lu5M6Sn18 (M = Co, Rh, and Ir) have been successfully growth by flux method. These caged type compound reveal superconductivity below Tc = 1.5 K, 4 K and 2.9 K for M = Co, Rh, and Ir respectively. It had been reported that R5Rh6Sn18 (R = Sc, Y, Lu), which exhibit superconductivity at 5 K (Sc), 3 K (Y) and 4 K (Lu), show intrigue time-reversal-symmetry broken in the superconductive state. It is interesting to compare the muSR results of Lu5Rh6Sn18, Lu5Co6Sn18 and Lu5Ir6Sn18, which possess different shells of d electrons and different Tc, to investigate time-reversal-symmetry broken mechanisms in Lu5M6Sn18 and their related dynamics.
DOI: 10.5286/isis.e.rb1800081
title: NTC 2018 Proposal Example 11

description: Please Ignore. This is just for setting up ERA's ready for the Neutron Training Course
DOI: 10.5286/isis.e.rb1810079
title: Evolution of magnetic ordering in the layered oxide arsenide Sr2CrO3CrAs

description: This experiment will probe the evolution of magnetic ordering in Sr2CrO3CrAs, a compound containing Cr2+ moments in arsenide layers and Cr3+ moments in oxide layers. We will use temperature dependent measurements on WISH to probe the magnetic ordering on the two sublattices and whether there is any interaction between the two as well as any effects of the magnetic ordering on the crystal structure. We will compare the behaviour with that of related oxide arsenide and oxide chalcogenide compounds.
DOI: 10.5286/isis.e.rb1810149
title: Quantifying the volume isotope effect in high-pressure forms of ice

description: Water ice forms a remarkable diversity of structures, occurring in as many as 17 crystalline forms. Water ice also shows other interesting and unusual properties. For example, it is well known that ice Ih (the form found in glaciers and in domestic freezers) is less dense than its own liquid. What is less well known is that ice Ih shows negative volume thermal expansion below ~ 60 K (i.e. the crystals shrink as they are heated) and that it has an anomalous volume difference due to isotopic substitution - the molar volume of D2O is larger than that of H2O, rather than the more usual situation in which the volume is decreased by substitution of the heavier isotope. Recent Computer simulations have predicted that similar isotope effects will occur in high-pressure forms of ice; the aim of this proposal is to determine whether this is indeed the case.
DOI: 10.5286/isis.e.rb1810804
title: Cs mixed cation lead perovskites

description: Organic-inorganic hybrid halide perovskites combine the optoelectronic properties commonly associated with high performance semiconductors with materials synthesis or processing routes involving very simple methods, including solution-based chemistry making them ideal materials for applications in solar cells . Since the first reported hybrid perovskite ( general formula ABX3) methylammonium lead iodide (MAPbI3), many variants have been synthesised, most employing a mixture of cations A+ = MA+/FA+/Cs+, Certified device efficiencies have risen to 22.1% in five years ( higher than commercial silicon based devices) and these "champion" systems contain a mixture of A-type cations.This experiment will determine the detailed structures of the "champion" materials contained within these high efficiency solar cells.
DOI: 10.5286/isis.e.rb1810868
title: Probing the structure/function relationship of NhaA protein incorporated into tethered lipid bilayers

description: We propose to perform combined measurements of neutron reflectometry (NR) and impedance spectroscopy (IS) to investigate the structure/function relationship of tethered bilayer lipid membranes (tBLM) on gold substrates with incorporated membrane transport proteins. This biomimetic membrane system is the core of the bio-fuel cell that we are developing to create energy in a bio-inspired way. Previous experiments have shown that lipid bilayers with a high fraction of cardiolipin show interesting properties for electrochemical application and that the incorporation of the sodium proton antiporter protein, NhaA, is possible. We want to extend the study to different lipid compositions, protein incorporation methods and tethered lipid molecular composition to optimize the membrane-protein system in terms of stability, efficiency in protein incorporation and electrochemical properties.
DOI: 10.5286/isis.e.rb1820019
title: Assessing a new system of hard sphere colloids using spin-echo SANS

description: We have recently developed a new system of refractive-index matched nanoparticles. This system has advantages over a extensively used one of polymer latexes; ours 1) can be prepared directly in the solvent of interest and 2) consist of a single polymer molecule in a single solvent. The particles are very interesting optically, as they are essentially transparent at all concentrations; our studies have been up to 50% by volume. However, more importantly for physical scientists, they particle interactions are minimized, making them, as far as is experimentally possible, equivalent to hard spheres. The next challenge in establishing them as a model system is verifying that the nanoparticles interact as hard spheres. Spin-echo small-angle neutron scattering (SESANS) is a uniquely suited tool to characterise the interparticle interactions.
DOI: 10.5286/isis.e.rb1820092
title: Understanding absorption of the energetic compound 3-Nitro-1,2,4-triazol-5-one (NTO) for industrial wastewater remediation

description: Insensitive munitions (IM) are munitions that will not react violently to accidental insult, thus they are relatively safe to handle and store. Ongoing research into IM has led to a resurgence of interest in the insensitive energetic material (secondary explosive) 3-Nitro-1,2,4-triazol-5-one (NTO). Unlike many energetic materials, NTO is surprisingly soluble in water and this leads to high levels of contamination in waste water streams from the industrial production of NTO. We have recently shown that this contamination can be conveniently cleaned from water using inexpensive sorption media such as activated carbon and basic alumina. We propose to investigate how NTO molecules interact with the surfaces of these sorption media to better understand how to improve the efficiency of waste water remediation efforts and reduce environmental exposure.
DOI: 10.5286/isis.e.rb1820510
title: Rheo-SANS of folded maltose binding protein hydrogels

description: Hydrogels are formed by the self-assembly of cross-linked building blocks in water.By using a folded protein as the building block, we wish to harness the intrinsic and specific mechanical properties of the individual folded proteins. We propose to use Rheo-SANS on the instrument SANS2d to investigate theeffect of stress on the architecture of hydrogels made using folded, globular maltose binding proteins. Our aim is to gain insight into the connection between the structure of the hydrogel network and its mechanical properties. This new information is crucial in building up a cross length scale understanding of the mechanical properties of a protein hydrogel, and will allow us to determine design parameters (specifically cross-link density and location on protein). This will allow the development of novel hydrogels which will have great potential in healthcare applications.
DOI: 10.5286/isis.e.rb1820528
title: Characterisation of biocompatible hydroxy double salts

description: In our quest to generate novel drug delivery systems, we have synthesised two novel, non-toxic inorganic systems in form of hydroxy couble salts (HDSs) from biocompatiple divalent metals. The new HDSs showed remarkable drug release profile in conditions that mimic passage through the human gastrointestinal tract. Whilst the metal positions could be determined in both the tetrahedral and octahedral positions, the position of the chloride counterion and more importantly the H atom positions are not clear. We thus propose to refine the crystal structures of the new HDSs from neutron diffraction data collected on POLARIS, which will allow the precise location of H atoms and resolving the counterion position. This will enable us to run molecular dynamics simulations for the prediction and improvement of drug release from HDSs under simulated physiological conditions.
DOI: 10.5286/isis.e.rb1820553
title: Revealing Structural Distortions driven by Oxygen Hole States in Perovskite Antimonates

description: We propose elastic neutron powder diffraction experiments on perovskite antimonates (Ba,K)SbO3. Main-group oxide perovskites have attracted intense research interest due to their novel physical properties including high-Tc superconductivity and oxygen hole states. Recently, we have synthesized (Ba,K)SbO3 for the first time, and found that the undoped compound BaSbO3 may possess a characteristic structural distortion due to the presence of oxygen holes. High-resolution diffraction experiments at WISH will enable us to precisely determine the crystal structure of (Ba,K)SbO3. Our results will be useful to understand the important role of oxygen holes and its link to high-Tc superconductivity among the main-group oxide perovskite families, and can be applied to a design principle for new oxide superconductors.
DOI: 10.5286/isis.e.rb1820559
title: Surfactant Modified Salivary Pellicles

description: Salivary films are (mostly) proteinaceous nm-thick films that form on any type of surface upon exposure to saliva. The role of the pellicle is manifold. Among its functions, hydration of the underlying tissues is often listed. Indeed, the hydration of salivary films was recently proved by a neutron reflectometry study by the applicants. This proposal focuses on the interaction between salivary films and surfactants used in oral health products. The use of these compounds has been related to the occurrence of mucosal damage in the oral cavity. Thus, it is of high interest to identify and use surfactants with the lower adverse effects. In this context, we intend to use neutron reflectometry to study how surfactants of different ionic character interact with salivary films and influence their hydration and, therefore, their protection of oral mucosa.
DOI: 10.5286/isis.e.rb1820565
title: Elucidating the Membrane Interaction Mechanism of Chloride Intracellular Channel Proteins

description: Chloride Intracellular Channels (CLICs) are a family of 6 proteins that have in common a C-terminal CLIC module and chloride-selective ion channel activity. CLIC1 is a 241 amino-acid protein involved in the regulation of the cell cycle, in particular it is overexpressed in a number of cancer cells. However, to date little information exists as to its structure and the factors that influence its insertion into membranes. Here we propose to study non-oxidised CLIC1 at pH 5.5 and 7.4 against two membrane compositions (i) PC:PE:Chol and (ii) PC:Chol. This will be used in combination with a broad range of ongoing biophysical characterisation to establish the mechanism of CLIC1 chloride channel formation, as well as the factors influencing it. This will be an initial step to understand how CLIC1 functions in tumour cells and will allow specific treatments to be designed to interrupt it.
DOI: 10.5286/isis.e.rb1710021
title: Improper ferroelectricity in hexagonal tungsten bronzes

description: Ferroelectrics are an important class of materials in modern electronics. Their application range from simple capacitors to ultrasonics transducers and sensors to memory devices. New ferroelectric materials and understanding the structural mechanisms of ferroelectricity in these, are a key step in their exploitation for future devices.The aim of this experiments is to understand the recent "improper" ferroelectricity exhibited by a family of tungsten bronze oxides compounds.
DOI: 10.5286/isis.e.rb1710031
title: Vibrational Spectroscopic Analysis of NbOPO4Hx and Ru/NbOPO4Hx catalysts for Improved Lignin Upgrading

description: Lignin valorization is receiving increasing attention. We request 7 days on TOSCA to carry out inelastic neutron scattering (INS) study of two key chemical processes in lignin upgrading: (i) the hydrolysis of 2-(2-methoxyphenoxy)-1-phenylethanol (lignin model compound 1 with -O-4 linkage) over an acidic NbOPO4Hx catalyst and (ii) the hydrocracking of biphenyl (lignin model compound 2 with 5-5 linkage) over Ru-loaded NbOPO4Hx catalyst. The proposed study will investigate the vibrational spectroscopy of the catalysts and their interaction with the corresponding guest molecules upon binding to the surface. In particular, this study aims to reveal the scientific origin of the high activity of NbOPO4Hx in the hydrolysis of 1 (1) and Ru/NbOPO4Hx in the cracking of 2 (2), leading to improved lignin valorization with significant potential market value.
DOI: 10.5286/isis.e.rb1710091
title: Skyrmion phase dynamics in the beta-Mn-type system Co8Zn8Mn4

description: Skyrmions are topological objects which have been shown to exist in the spin textures of a range of magnetic materials. As we have recently demonstrated in our transverse field muSR work on these systems, muSR is a promising method for exploring the physics of skyrmion lattices. Here we propose to to complete our investigations of slow dynamics in the beta-Mn-type magnet Co8Zn8Mn4 via the use of longitudinal field muSR.
DOI: 10.5286/isis.e.rb1710205
title: Exploration of the pressure-induced amorphization and glassy states of THF-clathrate II.

description: Clathrate hydrates (CHs) are ice structures in which water molecules (host) form cages through hydrogen bonds.  The cages can accommodate various types of molecules (guests), e.g. gases such as hydrogen and methane, and CHs with hydrocarbons exist naturally in large quantities in the deep sea floor sediments. We here explore the changes in structure when the crystalline ice host structure becomes amorphous (disordered) when pressure increases to 10 000 times atmospheric pressure at temperatures below -140 C, and also further changes as the amorphous state is heated. One objective is to determine if the guests remain in an ordered array in the amorphous ice structure.  Another is to observe the changes in structure when the water molecules start to move on heating. In particular, if the state transforms into an ultraviscous liquid with the guest molecules in an initially ordered array