cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.5286/isis.e.rb1761001
title: Optimization of the composition and firing temperature of B4C ceramics to be used as shielding material at ESS

description: We propose a characterization study for checking the final optimization of the composition and firing temperature of a functionalized ceramic enriched with B4C powder to be used as a shielding material in the construction of the ESS beam-line hutches. The same material could find useful application in other pulsed neutron scattering facilities like, for example, ISIS, SNS, and J-PARC. The measurement will consist in the intensity analysis, with respect to the spatial coordinates and energy, of the transmitted neutron signal through newly prepared types of ceramic containing boron. This project is supported by the CNR-ESS in kind activity.
DOI: 10.5286/isis.e.rb1820024
title: Muon spin relaxation study on the heavy-fermion superconductor Ce3PtIn11

description: Coexistence of magnetic ordering and superconductivity (SC) is a long standing puzzle in condensed matter physics. Ce3PtIn11 exhibits two successive antiferromagnetic (AFM) orderings at TN1= 2.2K and TN2 = 2K  followed by a superconducting  transition at 0.33K. The bulk nature of SC transition is confirmed by a sharp anomaly in the heat capacity at TC~ 0.3K. We anticipate unconventional nature of superconductivity in Ce3PtIn11 due to interplay between AFM and SC orders. Therefore, we propose to carry out rigorous µSR study on Ce3PtIn11 using the MUSR spectrometer.
DOI: 10.5286/isis.e.rb1820065
title: Field induced pinch points in the quantum spin liquid Ca10Cr7O28

description: Ca10Cr7O28 is a quantum spin liquid  characterised by the absence of static magnetic order where the spins are in coherent dynamical motion in the ground state. This state originates from the frustrated breathing kagome bilayer lattice of spin-1/2 Cr5+ ions which hosts competing interactions. The excitations are broad and diffuse reminiscent of spinons, however in a magnetic field they sharpen into spin-waves modes. Three pairs of gapped modes exist, the lowest energy pair condenses into the ground state at low field and is responsible for the spiral spin liquid behaviour. Theory predicts that the other modes host unusual dynamical spin liquids which would give a kagome spin liquid characterised by a pinch-point pattern if they were to become gapless. The aim of this proposal is to test these ideas by measuring the gapped and dispersionless pinch point modes predicted at high fields.
DOI: 10.5286/isis.e.rb1820367
title: Singlet fission materials as active quantum dot ligands for photon multipliers

description: Our research aims to develop plastic films that change the colour of the light that passes through them, not by absorbing certain wavelengths of light, as a simple colour filter would, but by converting light of one wavelength to another without losing any energy. Such a film, applied to a silicon solar cell, could make it up to 30% more efficient. To do this we need to make semiconductor nanocrystals, coat them with a very thin layer of an organic semiconductor so the two materials are in molecular contact. Then we have to disperse these tiny composite nanoparticles in a clear plastic film, as evenly as possible and without clumping. Small angle neutron scattering allows to pick out the shapes of the composite nanoparticles and their component parts, and the way they interact each other, helping us to design routes to make these "photon multiplier" films.
DOI: 10.5286/isis.e.rb1820406
title: Inelastic Measurements of a Frustration Stabilised 1D Ordered Magnetic State

description: Magnetic chains are playgrounds for unconventional physics but emergence of 1D order in cannonical systems is associated with full 3D magnetic order. Uniquely, below 1.6 K, Tb(HCO2)3 is host to an ordered 1D Ising magnetic state, which is possible due to frustrated antiferromagnetic coupling between chains. As the weaker antiferromagnetic coupling becomes more significant below 1.0 K this frustration appears to be partially relieved by spin canting, leading to the emergence of a stripped phase. The structures of magnetic phases of Tb(HCO2)3 are becoming clearer but understanding of the energy scale of its low energy excitations is very limited. We will use the low energy  LET spectrometer to probe each of the magnetic states of Tb(HCO2)3 to understand the energy scale of the interactions in this material to understand its dynamics and support theoretical studies of this unique compound.
DOI: 10.5286/isis.e.rb1820441
title: Pressure and Temperature dependence of the CsPb(IxBr1-x)3 perovskites: candidate materials for stable and efficient solar cells.

description: Halide perovskites have been the focus of an intense research effort, ever since the discovery that they can be employed to fabricate highly efficient solar cells.  One of the key challenges is to produce materials that are chemically and structurally stable, yet have optimal optoelectronic properties.  This effort is hampered by the almost complete lack of experimental data about their basic thermodynamic behaviour as a function of pressure and temperature - the classic clean variables through which stability is tuned.  Here we propose a neutron powder diffraction study as a function of pressure and temperature of the fully-inorganic CsPb(IxBr1-x)3 perovskite - a promising alternative to the popular organic-inorganic hybrids.  Key information obtained in this experiment will be later compared with first-principle calculations to define a route towards better materials properties.
DOI: 10.5286/isis.e.rb1820492
title: Magnetic excitations near quantum criticality in CeRh6(Ge1-xSix)4

description: In Ce-based heavy fermion materials, there is competition between the interactions which lead to a magnetically ordered arrangement of the Ce magnetic moments, and the hybridization between the local moments and conduction electrons, which quenches the local moments. Sometimes the magnetic transition can be tuned to zero temperature at a quantum critical point (QCP), where unusual properties arise due to quantum fluctuations. CeRh6Ge4 orders magnetically at a low temperature of 2.5 K, but by swapping Si for Ge, the magnetism is suppressed and eventually disappears, likely at a QCP. We propose to measure doped and undoped samples using inelastic neutron scattering, so as to characterize the nature of the magnetic ground state and crystal field excitations. This allows for the role of hybridization to be understood, and for the unusual spin fluctuations near a QCP to be probed.
DOI: 10.5286/isis.e.rb1820499
title: Structural changes of PdRu alloy nanoparticles caused by catalytic reactions

description: We are proposing 4 days of beamtime on GEM/Polaris to conduct the neutron powder diffraction experiments on PdRu alloy nanoparticles supported on CZ (CeO2-ZrO2) before and after the catalytic reactions at 400 °C with 3 different flow gases which are similar to actual exhaust gas of cars. PdRu alloy nanoparticles are expected to be high-performance and low-cost catalysts to remove CO and NOx in exhaust gas of cars. However, its endurance strongly depends the compositions of the gases (amount of CO for the stoichiometric reactions) and this mechanism must be clarified before practical use. The diffraction pattern and derived pair-distribution functions will provide direct information on the structural change caused by the reactions. The large difference between the neutron scattering cross sections of Pd and Ru and the high neutron intensity of GEM are keys in the present experiment.
DOI: 10.5286/isis.e.rb1820612
title: muSR characterisation of the first fully-organic triangular-lattice quantum spin liquid

description: The most successful recipe to date for making a quantum spin liquid (QSL) is a triangular lattice of molecular-dimer radicals tuned to behave as a weak Mott insulator. Two previous examples use dimers of BEDT-TTF molecules and a further example uses dimers of Pd(dmit)2 molecules. Recently another QSL has joined this list. This new system is based on dimers of cat-EDT-TTF, an asymmetric modification of BEDT-TTF. It has some unique properties, such as dimer spins being produced by charge transfer to hydrogen atoms, which in turn provide coupling between the layers via hydrogen bonding. It is also the first fully-organic triangular-lattice QSL, with no metal atoms anywhere in the structure. We propose to use ZF, LF and TF muSR to characterise this novel QSL and compare its properties with those of the earlier examples
DOI: 10.5286/isis.e.rb1820636
title: Muon spin relaxation investigation of triangular-lattice antiferromagnetic Fe3PO7

description: A recent hot topic in condensed matter is the discovery and successive study of skyrmions in materials such as MnSi or Cu2OSeO3. By tuning the magnetic field and temperature, the magnetic defects form a periodic lattice, the skyrmion crystal. Part of the excitement stems from the possibility of harnessing the topological aspect of these spin textures as a promising avenue for spintronics technology.  These special states sit near more conventional incommensurate helical structures. Recent work on the noncentrosymmetric Fe3PO7 whose lattice contains AFM coupled triangular Fe3+ ions suggests that it hosts nanosized helical magnetic domains with abundant magnetic defects below 163K. However, its precise magnetic structure is still unclear as conical and helical structures are suggested.  Our proposal is dedicated to understanding the magnetic configuration and topological defects in Fe3PO7.
DOI: 10.5286/isis.e.rb1868047
title: μSR Study on Superconducting IrGe

description: In recent times, materials with low-lying phonon (for instance K2Os2O6 [1]) have attracted immense interest in an aim to discover high transition temperature TC superconductors. The so-called rattling mode is known to enhance the electron-phonon coupling and hence the superconducting transition temperature, TC. Very few superconductors fall into this category, therefore the exact pairing mechanism and guiding principle to design such a material remains unclear. Preliminary studies on 5d transition metal germanide, IrGe, indicate the presence of low-lying phonon, and therefore offer an opportunity to study the detailed pairing mechanism [2].[1] Z. Hiroi et al. Phys. Rev. B 76 (2007) 014523.[2] D. Hirai et al. Journal of the Physical Society of Japan, 82 (2013) 124701.
DOI: 10.5286/isis.e.rb1869001
title: Spin-echo encoded neutron refraction of air bubbles in a fibrous protein gel

description: Calcium caseinate is a promising candidate to be developed into a meat analogue. When the dough like protein gel is subjected to mild shear and heat, it turned into a pronounced fibrous structure with lots of air bubbles entrapped in it. Plenty of effort has been spent to characterise the fibres, it was not until recent that the role of air bubbles are being noticed. These air bubbles are prolate spheroid like, with the long axis being parallel to the shear direction. We speculate the deformation degree of these air bubbles is correlated with the anisotropy index of the fibre. Thus, understanding the distribution, shape and size of the air bubbles can provide complimentary information for a complete picture on the structure of the fibrous protein gel. The SESANS mode on LARMOR will be used to detect the refraction of the neutrons when going through those air bubbles.
DOI: 10.5286/isis.e.rb1910071
title: Interactions between Designed Antimicrobial Lipopeptides and Inner Membrane Leaflets of Microorganisms by Neutron Reflection

description: Neutron reflection will be used to reveal the structural changes from different inner membrane leaflet models upon interacting with a group of antimicrobial lipopeptides with different hydrophobicity. The use of partially deuterated peptides and lipids will help improve interfacial structure resolution. We hypothesize that their different structural features implicate how they interact with bacterial membranes and kill them. NR is the only technique that can determine the amount and distribution of these represent AMPs once bound. We request 4 days on Surf to complete this work.
DOI: 10.5286/isis.e.rb1910366
title: The Effect of the Head Group on Multilayering of Alkanoic Alkyl Ester Sulphonates

description: We have shown that under certain conditions multilayer adsorption of surfactants occurs at the air-water interface. in which case the system becomes a powerful wetting agent (it will wet Teflon). A range of useful technological properties follows from this, e.g. more effective detergency, and since the phenomenon seems to be associated with more charged ions such as calcium and aluminium, hard water would enhance detergency in contrast to the usual reduction. An added advantage would be to do this with renewable surfactants. The alkyll ester sulphonates are renewables from palm oil and we have shown that the C14 and C16 methyl esters have a rich multilayer surface phase diagram with aluminium. The ion interaction is crucially dependent on the head group size and shape and we propose to tune the interactions via the ester group.
DOI: 10.5286/isis.e.rb1910539
title: In situ neutron diffraction study of residual strain evolution around a non-uniform crack tip subjected to a tensile overload

description: This project focuses on the development of new numerical modelling techniques for fatigue crack growth and in particular, non-uniform crack front evolution and crack growth through complex, through-wall residual stress profiles. Ultimately, the aim of the combined numerical-experimental research programme is to improve guidance in existing codes and standards (e.g. R6 and BS7910) to reduce the potential over-conservatism of fracture mechanics and fitness-for-service assessments.
DOI: 10.3886/e109121v1
title: Pre-service and in-service teachers’ beliefs about teaching and learning

description: Dataset from a questionnaire that aims to evaluate
pre-service and in-service teachers’ beliefs about teaching and learning is included. The
questionnaire has 28 items with a 5-point Likert-type scale. Items were distributed
across seven underlying factors: motivation, evaluation, socio-emotional
aspects, classroom climate, teacher’s role, student’s role and methodology. 641
responses by pre-service and service teachers from 32 different countries were recorded.<br>
DOI: 10.5286/isis.e.rb1567514
title: Ultra-slow muon production with room-temperature thermal-muonium-emitting material
DOI: 10.5286/isis.e.rb1610052
title: Fractionalized spin excitation and crystal electric field study in the rare-earth triangular quantum spin liquid candidate: YbMgGaO4

description: A new rare-earth triangular quantum spin liquid (QSL) candidate, YbMgGaO4, has an odd number of electrons per unit cell and spin-orbit entangled effective spin-1/2 (Yb3+). Recently, we have, for the first time, successfully synthesized powder samples and grown high-quality single crystals. Our early studies on magnetic property, heat capacity, and electron spin resonance characterizations have been reported. The measurements consistently and clearly suggested that YbMgGaO4 is a potential QSL with a spinon Fermi surface. Further sensitive and unique measurements, such as μSR and inelastic neutron scattering, are highly required to confirm the QSL ground state, explore and characterize the novel low-energy spin excitations at extremely low temperatures.
DOI: 10.5286/isis.e.rb1610231
title: Assembling floating, very sparsely tethered, bilayers.

description: The cell membrane is a very important structure in biology and many laboratory based model systems have been developed to study it using biophysical techniques. Our particular target is the bacterial outer membrane which is a significant barrier to antibiotics. Recently we have succeeded in making a realistic model but, to improve it further, we need to enlarge the water filled compartment below the model outer membrane which imitates the bacterial periplasm. Methods exist to anchor membranes above water layers but so far the density of anchoring molecule has been too high (&gt;40%) to properly form a realistic periplasm. Here we wish to test a new very sparse anchoring method which works with a surface containing only 1% anchoring molecules. If this works we hope to extend the length of the spacers to control the size of our model periplasm.
DOI: 10.5286/isis.e.rb1610279
title: Inelastic neutron scattering study of the metallic toroidal system UNi4B

description: There is considerable interest in understanding the magnetoelectric effect with the aim of developing technological applications. Until recently this has been limited to insulating systems, but the observation of a toroidal moment in metallic UNi4B opens up a new field of research. This material was previously studied in the 1990s, which revealed an unusual magnetic structure, leaving many open questions about its origins. With new interest in this material, we believe the time is ripe to reinvestigate the spin excitations in the system, as a preliminary step towards investigating their behaviour in applied magnetic and electric fields in the future. The detailed analysis of the magnetic excitations may allow the exchange interactions to be determined and thus be used to distinguish between the different proposed mechanisms for the toroidal magnetic order
DOI: 10.5286/isis.e.rb1610428
title: In-situ Formation of Fast Lithium Conducting garnets  via low temperature sol-gel chemistry

description: Increasing global population, global warming and depletion of fossil fuels have resulted in a growing need for better energy storage. Lithium-ion batteries are promising devices for this purpose, but have safety issues due to the presence of a liquid electrolyte.  We can overcome these by replacing this liquid with a solid-state lithium electrolyte with the same structure as the mineral garnet.  These are inert, unreactive oxide materials that will act as a heat sink to inhibit dangerous runaway reactions that can occur in batteries.  Neutrons are uniquely able to identify the complex mixture of materials that arise as these garnets are formed from heating reaction mixtures.  By examining these reactions we will be able to determine the cause of any instability in the garnet phase and so move towards safer, higher performance battery materials.
DOI: 10.5286/isis.e.rb1720029
title: Exploring Spin Correlations and Magnetic Order in a Novel Sodium-Ion Battery Cathode Analogue, KFe(C2O4)F, by Muon Spin Relaxation

description: The increasing global demand for portable energy means that the search for new electrode materials for rechargeable solid-state batteries is an important scientific challenge. Lithium-ion batteries are used in a variety of portable devices, but the limited supply of lithium and its rising cost have encouraged a shift in interest towards more sustainable sodium-ion battery alternatives. Recently, we have explored the synthesis and properties of various Fe2+-based polyoxyanionic systems related to phases suitable for use in sodium-ion batteries. Since high-spin Fe2+ is a magnetically active species, it is also vital that we explore the magnetic properties of these new materials in order to have a complete understanding of their behaviours. Here, we propose to explore the magnetic behaviour of the sodium-ion battery cathode analogue, KFe(C2O4)F, by muon spin relaxation.
DOI: 10.5286/isis.e.rb1720224
title: QENS Analysis of Proton Diffusion in Functional Metal-Organic Frameworks

description: The development of new functional metal-organic frameworks (MOFs) as complex proton conductor is receiving increasing attention worldwide. We aim to develop new solid proton conductors based upon stable MOFs and request 9 days on IRIS to study the motion of active protons in three isostructural porous MOF materials [MFM-300(M), M= Cr, Al and In] as a function of temperature. This proposed study will investigate the diffusion properties exhibited by these active protons from the MOF hosts. These three MOFs exhibit distinct proton conductivity (10-3 to 10-7 S cm-1 at 20 oC under 99%RH), although they have the same crystal structures, indicating the metal ions have significant impacts on the acidity of the MOF hosts. The proposed study aims to reveal the full nature of the proton conductivity by analysing the QENS data together with our MD modelling studies.
DOI: 10.5286/isis.e.rb1720380
title: The interaction of novel gold supraparticles with model lipid membranes

description: Engineered nanoparticles (NPs) found large application in medicine as theranostic materials for the diagnosis and therapy of many diseases. The understanding of the interactions of NPs with cell membranes is of fundamental importance both to tune the efficiency of NPs entry in the cell and limit their cytotoxicity. Neutron reflectometry (NR) is a powerful technique widely used to examine model membranes morphology and their response to different effectors. We propose the use of this tool to understand the nature of the interaction between novel  gold NPs and a model membrane whihc consists in a tether lipi bilayer, in vitro and in a relevant biological environment when NPs are in contact with proteins and form a new biological entity called protein corona NPs (PC).
DOI: 10.5286/isis.e.rb1720469
title: Exploration of the elemental analysis with negative muons in thin-film layers

description: Probing the elemental composition of thin-film layers with non-destructive methods is a serious challenge that has not yet a real answer. Negative muons have this capability, despite their limitation coming from the difficulties of implanting in materials having small volumes.Within this explorative proposal, we will develop the technique by measuring several multilayers of transition metals with grazing incidence experimental conditions. We will change the relative orientation of sample surface and incoming beam, and the collection of muonic X-rays following the muon implantation will reveal the feasibility of studies with this technique to measure the elemental composition of materials in the form of thin films.
DOI: 10.5286/isis.e.rb1768017
title: Investigation of Magnetic Structures in magnetoelectric multiferroic Gd0.5Dy0.5MnO3

description: Ferroelectricity in type-II multiferroics is induced by breaking of inversion symmetry by certain type of spin structure below the magnetic ordering temperature. Therefore, a knowledge of spin structure is imperative to find new magnetoelectric multiferroic materials. In RMnO3 (R=Dy and Tb), the interaction between Dy and Mn enhances the ferroelectric polarization arising from cycloidal spin structure of Mn-ions due to induced ordering of Dy-ions by Mn-ordering. In Gd0.5Dy0.5MnO3 system, our magnetoelectric measurement suggest that the Mn-polarization is suppressed at the R-ion ordering temperature. On the other hand, the low temperature ordering of R-ion itself induces independent electric polarization. Therefore, it is important to understand the magnetic structure of R-ion and Mn-ion at low temperatures.
DOI: 10.5286/isis.e.rb1768039
title: Unveiling competing magnetic interactions in Nd5Ge3: Muon spin relaxation

description: The physics across the phase transitions in solids has been of topical interest in the condensed matter physics. For example, liquid and vapor coexist along the vapor pressure curve and continuous liquid to gas conversion is possible beyond critical point. The knowledge of critical point is crucial in liquefying the gases in to liquids. In magnetic materials, the emergence of new magnetic phenomenon, at times, is observed by coexistence of different magnetic phases. Therefore, unraveling the magnetic phenomenon in such materials is always an interesting topic. The present proposal takes up the task to unravel the phase coexistence and first order phenomenon in Nd5Ge3 (rare-earth based compound) through muon spin relaxation (µSR) measurements by probing the spin fluctuations, low energy spin dynamics and long/short range magnetic orderings.