cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.5286/isis.e.rb1720376
title: Fractional spinon excitations in triangular-lattice quantum-spin-liquid candidate

description: A quantum spin liquid (QSL) is an exotic state of matter, which shows no magnetic order down to zero temperature but the spins are highly entangled. Its elementary excitations are fractional spinon excitations that show continuous spectra in neutron experiments. Experimental evidence has been found in 2D triangular-lattice YbMgGaO4, displaying dispersive spinon excitations with a clear upper edge. Here, we propose to study its isostructural compound TmMgGaO4 single crystals, which present paramagnetic behavior with Curie-Weiss temperature of around -20 K, indicating a stronger magnetic interaction than YbMgGaO4. Moreover, its non-Kramers doublet ground state can lead to a different spin Hamiltonian and a different topological structure can be expected. Thus, it is rather interesting to study the potential spinon excitations in TmMgGaO4 to provide another testing ground for QSL studies.
DOI: 10.5286/isis.e.rb1720396
title: Full reciprocal space mapping of the relaxational dynamics in CH3NH3PbCl3:

description: The organic-inorganic perovskites with chemical formula CH3NH3PbB(Br,Cl,I)3 have been implicated as being efficient photovoltaic materials.  Theoretical calculations and experiments performed by our group have indicated a strong coupling between molecular dynamics and electronic band structure and also the host Pb -based framework.  This proposal aims to obtain a full three dimensional map of the quasielastic scattering from the molecular motions at temperatures below and above the structural transition.  This will be used to obtain information on how the molecular motions are correlated in real space and related to ongoing work on powder samples.  The entire proposal requests 5 days of time (2.5 days at both temperatures).
DOI: 10.5286/isis.e.rb1810172
title: Non invasive characterization though neutron diffraction of ancient Indonesian Keris

description: The keris is the distinctive weapon of Malaysia and Indonesia. It is found in a variety of forms but, typically, it is an elongated dagger or short sword of slender proportions with a blade of rough pattern-welded texture sharpened on both edges.All good Southeast Asian keris are made of two sorts of metal, iron (or steel) and pamor welded together in intricate patterns and subsequently brought out on the polished surface of the blade by etching.Pamor, is the etch-resistant component traditionally used in the blades, and includes a variety of metals.In order to investigate the composite structure of the keris and the different types of pamor effectively used, we propose to analyze three keris provided by the Wallace Collection in London and one by a private collector whose typology has been extensively described in literature.
DOI: 10.5286/isis.e.rb1810321
title: Magnetic interactions in the room-temperature skyrmion material Co8Zn8Mn4

description: We propose an investigation of the spin-waves in the recently discovered room-temperature skyrmion material Co8Zn8Mn4.   The ground state of Co8Zn8Mn4 is a very long wavelength helix of wavelength 125 nm as shown by previous SANS measurements, and application of a magnetic field of between 100 and 500 G at T~ 290 K stabilises a skyrmion lattice phase.  Recent studies show that this skyrmion lattice is remarkably robust as a function of temperature, and is metastable on field-cooling down to zero temperature.  This makes Co8Zn8Mn8 a technologically interesting material, and understanding of the fundamental interactions is important.  We will perform Horace scans on MERLIN in RRM mode to cover a wide range of energy scales, and will need 4 days beamtime to complete this measurement.
DOI: 10.5286/isis.e.rb1810816
title: Interactions of Surfactant Mixtures with Phospholipid Vesicles: the Influence of Hydrophobic Chain Fluidity

description: Surfactants have been widely used in cosmetics, detergents and pharmaceutical industries. These applications are always accompanied by surfactant-induced skin irritation which is linked to surfactant interaction with the components of the outermost layer of skin: dead corneocytes and extracellular lamellar lipid. Therefore, for surfactant-induced skin irritation, the interaction of skin lipid with surfactants should be studied. In this proposal, phospholipid vesicles are been used as a first step to model the lipid in skin. SANS will be employed to study the interaction of phospholipid vesicle with cationic/anionic surfactant mixtures. We try to reveal how the surfactant mixture incorporate into and disintegrate the phospholipid vesicle and explain the observed efficacy of mixed surfactants.
DOI: 10.5286/isis.e.rb1720287
title: Denitrogenation of fuel oils using hydrated choline chloride:malic acid DES

description: Deep Eutectic Solvents (DES) are complexes of organic salts and neutral hydrogen bond donors. They are tuneable, low volatility liquids that are environmentally benign. Denitrogenation of fuel oils reduces nitrogen and sulfur oxide emissions from burning petrochemicals in internal combustion engines, but current processes are intensive. A greener denitrogenation process has been developed using DES. Remarkably, the DES can achieve higher extraction efficiency when it contains a small amount of added water. We have analysed data already for the pure DES used in this extraction: choline chloride:malic acid with and without water. Therefore, here we wish to study the structure of this DES containing a small-molecule nitrogen compound (indole) with and without water to discover the mechanism behind the high extraction efficiency of DES and hydrated DES.
DOI: 10.5286/isis.e.rb1770012
title: MuSR Investigation of Quantum Critical Point in Hole-Doped Pyrochlore Iridates,  (Y1-x-yCuyCax)2Ir2O7

description: Y227 is an ideal system to investigate Ir moments, mainly to study the presence of QCP, because the Y atom does not have a local magnetic moment. From the results of our resistivity measurement, the Metal-Insulator transition (MIT) seems to disappear around x = 0.20 at low temperatures below about 50 K. Thus, we suppose that QCP exists around x~0.20 in (Y0.95-xCaxCu0.05)2Ir2O7. We expect to discuss from this proposed study to achieve intrinsic information how the Ir moment is changing when the system changes to be metallic in order to confirm our current results and clarify phase diagram, especially the position of QCP.
DOI: 10.5286/isis.e.rb1810009
title: Investigating the diffusion of E-caprolactam in hierarchically-porous catalysts for the Beckmann rearrangement

description: Caprolactam (CL) is a high-value chemical and precursor to nylon-6. Industrially, a harsh, liquid-acid catalyst effects the Beckmann rearrangement of C6-oxime to CL, but the risks and inefficiencies of this process make solid-acid catalysts desirable. Whilst silicoaluminophosphates (SAPOs) show potential, their micropores suffer mass transport limitations. Hierarchically-porous (HP) SAPOs contain an auxiliary mesoporous network that enhances active site accessibility, whilst retaining the selectivity of the microporous bulk. An earlier QENS study revealed the contrasting mobility of C6-oxime in HP and microporous SAPO-5, with substrate-framework interactions in HP SAPO-5 hindering motion at higher temperature. Since product desorption is a key mechanistic step that shows dependence on the nature and strength of the acid sites, we now propose to study the mobility of CL in these systems.
DOI: 10.5286/isis.e.rb1810745
title: Determination of the crystal electric field scheme in geometrically frustrated lanthanide garnets

description: The magnetic ground state in geometrically frustrated lanthanide oxides is determined by the interplay between different magnetic interactions and crystal electric field (CEF) effects. We have recently the effect of chemical pressure on the magnetic properties of the frustrated lanthanide garnets, Ln3A2X3O12, by varying the non-magnetic cations A and X. Magnetic ordering features are observed for all garnets with Ln = Tb, Dy, Ho; however the nature of ordering varies for different Ln as well as for different combinations of A and X. The magnitude of exchange and dipolar interactions are found to be similar for all the garnets. Therefore it is postulated that the variations in magnetic ordering are caused by subtle differences in the CEF. We propose inelastic neutron scattering experiments on MERLIN to precisely determine the CEF levels for garnets with Ln = Tb, Dy, Ho.
DOI: 10.5286/isis.e.rb1810833
title: Studying the Temperature Dependence of The Slower μSR Frequencies in CsNiCl3

description: We seek to continue our study of CsNiCl3 to determine the nature of the two magnetic transitions.Previous experiments at PSI have shown there are two distinct muons sites, one with a fast frequency and another with a much slower frequency that is well suited to the ISIS time window. The data we have collected has proveded useful information, although more data is needed to fill in the gaps and to be able to give a more firm estimate of the order parameters. One problem is that at for the slow frequency, you can not see the damping at PSI since this is at the edge of what they can measure. Therefore our study has moved to ISIS, where we can unravel the behaviour associated with the two muon stopping sites.
DOI: 10.5286/isis.e.rb1620164
title: Charged nanogels interactions with model lipid membranes

description: In recent years nanogels show great potential as drug delivery systems. Especially dermal drug administration which is non-invasive, helps to avoid the first-pass effect with better patient compliance and allows continuous drug realise gain a lot of attention. Here we want to study the interactions between charged, pH and thermo-responsive nanogels with model lipid membranes mimicking skin. Those studies not only will allow better understanding the nanoparticle  lipid membrane transport mechanism but as well will help in risk assessment connected with nanoparticle exposure.
DOI: 10.5286/isis.e.rb1710496
title: Ammonia synthesis using lithium hydride-metal nitride composites: an in situ neutron powder diffraction study

description: The development of more active catalysts for the production of ammonia will have a worldwide impact on the energy cost of producing fertiliser. Composites of lithium hydride and transitions metals/metal nitrides have recently been identified as highly active ammonia synthesis catalysts. Their activity has been explained by a nitrogen-shuttling mechanism between the metal/metal nitride and lithium hydride, resulting in the formation of lithium amide. We request four days on POLARIS to measure neutron powder diffraction data on these catalyst composites during the ammonia synthesis reaction. These data will provide insights into the active form of the catalysts and the nature of their remarkable catalytic effect on this critical industrial reaction.
DOI: 10.5286/isis.e.rb1720114
title: The molecule state in the molecularly doped metals

description: Inelastic neutron scattering (INS) spectroscopy is an ideal technique for studying the interaction of a metal with ligands because the metal is essentially invisible to neutrons and therefore only the organic molecule is visible. It provide us the needed efficient tool for detecting the local environment for the metal-molecules interfacial interactions in the molecularly doped metals. The detailed information gathered on the adsorption sites of molecules on the metal surface of the forming nanocrystallites will reveal these special metal-molecule interactions in the 3D entrapment process.The detailed understanding of the 3D-entrapment mechanism will lead to better design of experiments which will allow the expansion of both the efficiency of existing composites and the development of new composite systems.
DOI: 10.5286/isis.e.rb1720311
title: Investigation on the air-water adsorption behaviour of N-acyl amino acid surfactants

description: N-acyl amino acids are promising anionic amphiphilic molecules with an improved toxicological profile in comparison to the most common used sulfate-based surfactants. Previous reflectivity measurements have evidenced some differences in the interaction of N-decanoyl surfactants with the bilayer as a function of the different polar head. We observed for C10LEU the insertion of surfactant into the lipid bilayer at concentrations below CMC and a complete lipid removal at concentration double of CMC. On the contrary, C10ALA and C10SER maintained the bilayer integrity up to a concentration of three times CMC. We propose here to determine by reflectivity measurements the adsorption at the air-water interface of these compounds. This information is essential for a full understanding of the different behaviour of the analysed N-decanoyl amino acid as regards cytotoxicity and membrane interaction
DOI: 10.5286/isis.e.rb1720463
title: Magnetic Ground state of a New Heisenberg-Kitaev Quantum Spin Ice Candidate

description: We propose to measure the magnetic diffraction pattern of the potential Kitaev spin liquid compound Li2RhO3. Moderate spin orbit coupling in the Rh4+ ion is expected to results in a ground state doublet which in combination with the honeycomb structure of RhO6 and edge-sharing octahedra, gives rise to highly directional Kitaev interactions. The resulting lattice is strongly frustrated and might be the reason why no long-range magnetic order has been found in this compound. Our goal is to measure the diffraction pattern to verify whether long-range magnetic order is really absent and to investigate the diffuse scattering as a function of temperature.
DOI: 10.5286/isis.e.rb1810055
title: Paramagnetic excitations in NaFe0.53Cu0.47As

description: NaFe0.53Cu0.47As is an antiferromagnetic Mott insulator which connects unconventional superconductivity and Mott physics. The magnetic fluctuations in the ordered state has been established previously, while the fluctuations above Tn is still unclear. Since the presence of short-range magnetic fluctuations is the key to understand the insulating electrical transport behavior in the paramagnetic state, studying the strength of paramagnetic fluctuations is crucial to elucidate the role of electronic correlations in NaFe0.53Cu0.47As. We propose to study the magnetic fluctuations in NaFe0.53Cu0.47As at 250K using MAPS, and we request 6 days of beamtime for our proposed experiment.
DOI: 10.5286/isis.e.rb1810188
title: The mobility of water in graphitic carbon nitrides

description: Carbon nitrides are emerging as an important class of materials with a variety of technical applications  The focus of this study are  polytriazine imide (PTI) materials, which are the only crystalline graphitic carbon nitrides that can be synthesised readily and reproducibly. These comprise a 2D network composed of planar layers with voids in these layers which form channels filled with Li+ and Cl- ions. A recent observation has been that the lithium and chlorinte can be removed from the PTI materials by washing with water. We can rversibly intercalate wate into these structures and the goal of this study is to establish the mobility of hydrogen within these modifoed and unmodified materials, both within channels formed by the triazine layers and between graphitic layers. Overall the the goal is to understand the influence of these guest atoms on the materials properties
DOI: 10.5286/isis.e.rb1710452
title: Confinement of Liquids within an Anodic Alumina Support

description: The structure of liquids in confined geometries is of significant interest to many diverse areas, for instance chemical catalysis (liquid-phase reactions inside porous materials), geology (gases under pressure, e.g. CO2), and biology (e.g. the freezing, or not, of water in inter-membrane voids). However, investigation of such phenomena is limited by the very nature of their confinement, the liquid being buried within the material of interest.While neutron scattering is able to probe the bulk material, making it an ideal probe for such confined systems, a second critical issue is the characterisation of the confining bulk at the nanoscale. In order for fundamental information on the confined liquid to be effectively revealed, the porous substrate must be well defined. Anodic aluminas potentially offer such well-defined pores, and so we propose to study common liquids confined therein.
DOI: 10.5286/isis.e.rb1720063
title: How complex is complex: an ALC study of a 10-mer helical peptide chain

description: There have been ALC studies on the interaction of muons with native proteins, but little systematic work that contributes understanding of how spectroscopic information alters with structure. However, to truly understand the applicability of the ALC method to native material one has tounderstand the limitations of the method in such complex bio-polymers. To test these limits, we wish to build on our phenylalanine study and use a short peptide that forms an alpha-helical structure. Using the sequence, Glu-Leu-Glu-Lys-Glu-Leu-Glu-Lys-Lys-Phe, we expect muonaddition to the Phe ring and C=0 species (backbone) only. By already studying coupling to Phe, we will be able to understand how addition of this acid to a C=O rich sequence alters the Phe resonance, understand the resonance signature from those muons tagging the backbone andmonitor both in the folded and unfolded state
DOI: 10.5286/isis.e.rb1720289
title: Surfactant self-assembly in mixed choline chloride:urea-choline chloride:glycerol deep eutectic solvents

description: Deep Eutectic Solvents (DES) are mixtures of organic salts and hydrogen bond donors, that form strongly hydrogen-bonded room temperature liquids. DES share many features with ionic liquids (ie. tunable physicochemical properties) which makes them viable green solvents that are less toxic than typical ILs. We have studied amphiphile self-assembly in DES with the aim of developing templated deep eutectic-solvothermal syntheses. We found that cationic surfactants were not soluble in choline chloride:urea DES, yet urea plays an active role in synthesis of inorganic oxides via decomposition, and this also degrades anionic surfactants in DES so they cannot act as templates. Cationic surfactants are soluble, and anionic surfactants suffer less decomposition, in mixtures of choline choride:urea-choline chloride:glycerol DES, so here we plan to study CnTAB and SDS micelles in this mixed solvent.
DOI: 10.5286/isis.e.rb1720413
title: Probing Consistencies in Li Solvation for Battery-Electrolyte Systems: Glymes to Polyethers

description: We request 5 days on Nimrod to determine the local environment of Li cations in a set of polyther solvents used as battery electrolytes. Through increasing the chain lengths of these polyethers, the so called Glymes, we hope to correlate their flexibility with coordination about Li in the solution phase. At present there only exists computational models of the lithium pair-distribution functions in these systems, and this study would thus represent the first experimental validation of existing models.
DOI: 10.5286/isis.e.rb1720478
title: muSR of a Quantum Spin Liquid based on the Hyperhoneycomb Lattice

description: The hyperhoneycomb lattice can be viewed as a 3D version of the 2D honeycomb and the new magnetic compound [(C2H5)3NH]2Cu2(C2O4)3 provides a rare example. Honeycomb type lattices are expected to support spin liquid ground states when favourable patterns of spin interactions are present. This can happen when spin orbit coupling is strong (as in the Kitaev model) or when next-nearest-neighbour interactions are a significant fraction of the nearest neighbour interactions (J2/J1~0.2-0.4), as appears to be the case here. Following Jahn-Teller distortion around the Cu sites, a 2D magnetic lattice emerges that is honeycomb-like. Various measurements show gapless 2D spin liquid character, including muon data down to 60 mK. Distinct sub-phases found within the spin liquid require taking further muon data in a set of LF scans between 50 mK and 15 K. This will allow a thorough test against theory.
DOI: 10.5286/isis.e.rb1768032
title: Muon spin relaxation study of Co-dopedCeCu2Ge2

description: In recent times, Ce based HF compounds have become a promising and active research field in condensed matter physics as one can drive the system towards quantum critical point (QCP) by applying external pressure or chemical doping. Near this QCP few systems are found to exhibit superconductivity which is thought to be mediated by magnetic fluctuations unlike conventional superconductors where phonons play the key role in governing superconductivity. In this frame work, Co doping in CeCu2Ge2 is quite exciting as it drives the system towards QCP. We have performed a systematic study on Ce(Cu1-xCox)2Ge2 and found a possible QCP near x= 0.1. Therefore, we propose to carry out µSR measurements on x=0.0, 0.1 and 1.0 samples to probe the magnetic ordering and spin fluctuations present in the sample near QCP.
DOI: 10.5286/isis.e.rb1810171
title: Identification of the intuitive forging methods and microstructural properties of Japanese Swords through quantitative multiphase analysis

description: The metallurgy of historic melee weapons (swords, in particular) is one of the most significant topics in archaeometallurgy because these objects were manufactured intuitively for a thousand years using the highest quality materials and the most advanced technology of their age. They remain among the best steel ever made. Japanese steel arms represent, probably, the most important topic in this field of historical metallurgy. We propose to analyse, on the INES diffactometer, four ancient Japanese swords pertaining to a private collector and renowned among the best ancient Japanese swords present in Europe and cited in several catalogues and bulletins of the European branch of the Society for the Preservation of Japanese Swords. We want to measure the composition and micro structural properties in different selected cross sections of the blades,
DOI: 10.5286/isis.e.rb1810491
title: The effect of bilayer rigidity on the interactions with perfluoroalkyl compounds

description: Perfluoroalkyl substances (PFASs) are used extensively in industrial products although have been identified as emerging pollutants accumulating in wildlife and environment. PFASs exhibit different uptake behavior in plants compared to worms and since it has been established that they aggregate in lipid-rich tissues, it is important to investigate the dependence of their interactions with different types of lipid that form cell membranes. As the first part of this project, we have studied the interaction of a wide range of perfluoroalkyl substances with saturated phospholipid, DMPC, as a simple model system for biological interfaces. The new experiment aims to study the interaction of PFASs with an unsaturated lipid, DOPC, which forms a softer bilayer and understand to what extent the rigidity and ordering of the bilayer can affect the interactions and incorporation of PFASs.
DOI: 10.5286/isis.e.rb1810861
title: The analysis of Indo-Persian armour in the Wallace Collection

description: Our long-term aim is a detailed study of the Oriental Arms & Armour in the Wallace Collection, London, which contains nearly one thousand items and is one of the most important collections of Indian arms and armour outside the subcontinent.In the collection, there are approximately 200 swords, 20 body armours, 50 helmets and shields of princely quality, and it is fundamental that any analyses are non-invasive.It is our intention to investigate in depth the quality and the kind of steel used for their production, and the different mechanical and thermal processes that were used in their manufacture. We propose to measure a first set of 12 pieces of Indo-Persian armour from the Wallace Collection in order to determine their phase distribution.