cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.5286/isis.e.rb1410433
title: Morphology and Phase Diagram of Thermoresponsive Polymer-Protein Conjugates

description: Using an enzyme mediated conjugation method we have prepared well-designed protein-polymer conjugates using a model protein, green fluorescent protein (GFP) with thermo-responsive polymers based on HPMA (N-2- hydroxypropyl methacrylamide)-Acetyl-HPMA (O-acetyl-N-2-hydroxypropyl methacrylamide) and a commercially available PNIPAM-NH2.In this proposal we wish to study in greater detail the self-assembly of these temperature responsive polymer-protein conjugates. Such investigations could be particularly useful to understand the structural properties of these materials as the molecular weight changes and how they respond to the polymers transition to a collapsed state at higher temperatures. The phase diagram of eGFP-copolymer conjugates will be mapped out with respect to copolymer composition and concentration effects as well as temperature and water content.
DOI: 10.5286/isis.e.rb1510027
title: Novel gels with supercritical carbon dioxide

description: This proposal is to probe the gel structure with High Pressure SANS (HP-SANS) using an in-line pressure cell. The ability to control the properties of supercritical CO2, particularly the system viscosity, is an area that holds much promise in the fields of enhanced oil recovery (EOR) and carbon capture and sequestration (CCS)1,2, as well as a potential replacement for volatile organic solvents. Progress in this field has recently been reviewed by Peach et al.3. This research has received external publicity through the UK government agency UK trade and Investment (UKTI)8 and is supported by an STFC funded studentship ST/L502613/1 - ¿Controlling fluid properties of dense CO2¿ and the G8 Research Councils Initiative on Multilateral Research Funding - G8-2012 - EP/K020676/1.
DOI: 10.5286/isis.e.rb1510059
title: Competitive adsorption of a Biosurfactant conventional surfactant mixture at the oil water interface.

description: We propose to study the competitive adsorption of a biosurfactant conventional surfactant mixture at the surface of an emulsion droplet in order to determine how these two surfactants compete at a hydrocarbon water interface. The key objectives are to see if the biosurfactant competes as well at this more realistic interface as it does under truly model conditions in the laboratory. The technique of Small Angle neutron scattering is particularly suitable as it allows the scientist to "tune out" the signal from the oil droplet and study only the surfactant on the outside. By using a combination of special labelling and a systematic study we will be able to measure the amount of each surfactant adsorbed which will in turn aid understanding which could ultimately lead to deployment in product emulsions such as skin lotions and foods.
DOI: 10.5286/isis.e.rb1510083
title: Spin dynamics in a doped S=1/2 Heisenberg Antiferromagnetic chain SrCuO2

description: We propose to microscopically study the role of defects on spin transport in one of the best approximations to the ideal antiferromagnetic Heisenberg s = ½ chain. By measuring the longitudinal muon relaxation in magnetic fields we will study the processes governing the dynamical properties. A range of temperatures and fields will be used to identify whether there are any crossovers between different transport regimes and to see if they are related to the new pseudogap energy scale which appears upon introduction of impurities.
DOI: 10.5286/isis.e.rb1510207
title: SANS Study of the interaction of non-ionic surfactants with wheat and barley waxes at different temperatures

description: We propose to make use of SANS to determine the influence the presence of cuticular plant waxes have on the size, shape and structural properties of various non-ionic surfactants. This work will help explain the wax removal and plasticisation processes that are observed as surfactant micelles are introduced onto plant surfaces, which resultantly significantly increase waxes permeability to water and active ingredients.Furthermore, we will use SANS to investigate how this affect changes with temperature, mimicking the environmental conditions plant waxes would experience. As the amorphous content of waxes is very sensitive to temperature change, we hope for exciting results. We request 4 days of SANS2D beam-time to complete the planned investigation.
DOI: 10.5286/isis.e.rb1510320
title: A complex model of the bacterial outer membrane containing oriented proteins and smooth LPS.

description: The Outer Membrane (OM) is found in bacteria which cause plague, cholera & Legionnaire¿s disease. It is important as; a barrier to antibiotics & the site of human-bacteria interaction. However bacteria are too small to allow us to do precise measurements of the structure and dynamics of this critical interface. Using neutrons as our eyes we have recently investigated OM models which imitate many aspects of the natural OM. This includes its structure where the outer surface is dominated by a molecule called lipopolysaccharide (LPS).  However the model is unstable if we use the very large versions of LPS found in some bacteria. This project aims to understand this by fixing the other components of the model to a surface and just allowing the LPS to assemble and disassemble. In this way we seek to understand what maintains the structure of the natural OM and thus improve our future models.
DOI: 10.5286/isis.e.rb1510425
title: Small-angle neutron scattering studies of phase separation in Fe-Cr based alloys

description: Iron-Chromium is an ideal model system to improve the fundamental understanding of phase separation with vital engineering applications. For instance, ferritic and duplex stainless steels, with Fe-Cr basis, suffer from embrittlement, and cemented carbide cutting tools and coatings can be strengthened, using phase separation. Thus, a better fundamental understanding of the kinetics of phase separation has large technical implications e.g. in power generation applications (stainless steels) and in metal cutting applications (cemented carbides and coatings). The principal investigators have a large fundamental activity within this field and large industrial collaborations in both areas. However, we are lacking insight in the dynamics of phase separation and this is the purpose of the proposal. Neutron scattering provides the only viable method to study the early-stage kinetics.
DOI: 10.5286/isis.e.rb1510528
title: Effect of galvanostatic electrochemical control function on metal alloy deposition

description: The proposed project is aimed at determining the nucleation/growth processes and structures (metal distributions and solvent population/distribution) of metallic films deposited in situ by different electrochemical protocols. We have successfully completed NR investigations of potentiostatic and potentiodynamic electrochemical methods in the deposition and stripping of single metal systems of Ag, Cu and Sn as well as alloy and multilayer systems of Ag/Cu and Cu/Sn all of which have significant industrial interests. The outcomes of these experiments have provided insights into the early stages of deposition and on the alloying/segregation of components within the deposited layer. Since deposit structure is in general a function of electrochemical protocol, our aim is to complete the exploration by making NR measurements during deposition under galvanostatic (constant current) control.
DOI: 10.5286/isis.e.rb1561017
title: Investigation of single crystal diamond detectors at high temperature under intense and long lasting neutron irradiation
DOI: 10.5286/isis.e.rb1610169
title: WATER DYNAMICS IN FERROFLUIDS

description: Magnetic fluids are used in conjunction with applied magnetic fields in several medical applications including drug and gene delivery, imaging and hyperthermia cancer therapy.  Ferrofluids consisting of iron oxide nanoparticles suspended in water are biocompatible and already clinically approved. In this context, we propose to study the effects of the application of magnetic fields similar to those used in medical applications on the dynamics of water molecules in ferrofluids.
DOI: 10.5286/isis.e.rb1610426
title: The coupling of spin and charge correlations in La2-xSrxCuO4

description: Charge density wave (CDW) order has recently been established as a generic feature of  high-temperature cuprate superconductors. It occurs near 1/8 doping and has been observed by x-rays which see it appearing below the pseudogap temperature. CDW order competes with the superconductivity. Some cuprates also show incommensurate spin density order (SDW).  In La2-xSrxCuO4, this occurs for similar dopings as the CDW order. The co-existence of the two types of order suggests that they are microscopically intertwinned and are due to static stripes involving spin and charge modulations.  This is a continuation proposal which will search to see whether the spin and charge orders are also connected in the dynamics of 1/8 La2-xSrxCuO4. In particular, we will see whether the magnetic excitations are modified as charge correlations develop.
DOI: 10.5286/isis.e.rb1610502
title: Using negative muons as a non-destructive probe of material composition

description: Elemental analysis is a process in which a sample is analysed for its composition. Often this is accomplished by destructive and damaging techniques. Clearly, such techniques are not desirable for valuable items (either scientific or monetary). Therefore, techniques of non-destructive bulk elemental analysis are desirable, for example in engineering, Earth and archaeological sciences. Negative muons offer the possibility of a non-destructive multi-elemental analysis.
DOI: 10.5286/isis.e.rb1661008
title: Optimization of the composition and firing temperature of B4C ceramics to be used as shielding material at ESS
DOI: 10.5286/isis.e.rb1670532
title: Study of the spin dynamics of a honeycomb ruthenate using spin polarized muons
DOI: 10.5286/isis.e.rb1720042
title: CO2-philic Low Surface Energy Surfactants for applications in Enhanced Oil Recovery (EOR)

description: In recent years, there has been an enormous interest in the study of surfactants for supercritical CO2 (scCO2). One important potential application of these materials is in Enhanced Oil Recovery (EOR), where stabilised CO2 microemulsions are formed by injecting CO2 to oil reservoirs under harsh, high pressure-high temperature (HPHT) conditions. This proposal aims to explore cheaper and more environmental friendly surfactants for CO2 microemulsion formation at HPHT, using branched, low surface energy surfactants. This project is supported by a Sêr Cymru II Welsh Fellowship part-funded by the European Regional Development Fund (ERDF).
DOI: 10.5286/isis.e.rb1720146
title: Continuation of the low-frequency fluctuations muSR study in Mn-doped La1-yYyFeAsO0.89F0.11 superconductors (RB1620216)

description: The aim of the experiment is to study, in low magnetic fields, the very slow spin fluctuation (MHz range) present in the normal phase of La0.8Y0.2LaFe1-xMnxAsO0.89F0.11  superconductors detected by 19F nuclear magnetic resonance spin-lattice relaxation time (1/T1). LF muSR measurements should confirm that the already observed enhancement of ZFmuSR  relaxation is indeed due presence of the low frequency fluctuations.
DOI: 10.5286/isis.e.rb1720201
title: Investigating the diffusion of liquids within an Anodic Alumina Support

description: The effect of confining liquids has great importance in many areas and is  particular interest in liquid phase heterogeneous catalysis. Metal catalysts supported on porous materials are widely used for instance in the catalysed hydrogenation of benzene to cyclohexane1, a reaction of significant commercial interest due to the use of cyclohexane as a precursor in the production of nylon, as well as environmental applications such as the removal of benzene from fuels. The diffusion process is often the rate limiting step in any catalytic reaction and so investigation of the diffusion of liquids inside the pores is of critical importance. The use of a support structure with such regular pore structure and pore size distribution shows clear advantages in terms of both diffusion processes and dispersion of metal catalysts. It is therefore of great interest to measure the diffusion process.
DOI: 10.5286/isis.e.rb1720353
title: Magnetism in NaTiO2

description: NaTiO2 has been predicted to have a variety of unusual magnetic states, depending sensitively on the details of the crystal structure and interaction strength between the magnetic Ti3+ ions. The material is particularly interesting because it also has potential battery applications. However, there have been remarkably few studies carried out on this system. Our collaborators have synthesized high quality NaTiO2, which exhibits transitions, assumed to be structural, at temperatures nearly 50 K higher than previously studied samples. We propose to carry out muon spin relaxation measurements to characterize the low temperature magnetic state of this system. The results will be correlated with parallel studies via neutron scattering of the crystal structure and magnetism.
DOI: 10.5286/isis.e.rb1761003
title: The analysis of Medieval European helmets in the Wallace Collection and elsewhere

description: Our long-term aim is a detailed study of the Arms & Armour in the Wallace Collection, London, which contains over two thousand items and is one of the most important collections of European arms and armour in Europe. Many items of plate armour can be investigated non-invasively by metallography, depending on the shape of the plates.  However, many helmets have rolled edges and so metallography is difficult without taking samples. so only neutron diffraction is an ethical method of analysis. There are a number of helmets which stylistically might be products of the Imperial Workshop at Innsbruck, but their makers marks have not survived.  Characterising them as having microstructures of tempered martensite (in the late 15th century) would be strong evidence for their having been made in Innsbruck.
DOI: 10.5286/isis.e.rb1800026
title: The structure of solvents around graphene oxide nanoparticles

description: Graphene oxide is an important starting material for developing chemically modified graphene for use in a variety of important technical applications that include energy-related materials sensors, biomedical materials and polymer compositions for fuel cells. Graphene oxide can be formed into a dispersions in solvents including water and these concentrated dispersions of graphene oxide nanoparticles remain stable for weeks. It is becoming increasingly evident that for nanomaterials simple models of colloidal suspensions are inappropriate since the structure of the solvents has a strong influence on particle behaviour as their dimensions become smaller. In this proposal we will use neutron diffraction to examine the structure of the water solvations shell surrounding graphene oxide nanoparticles using different isotopic compositions of water.
DOI: 10.5286/isis.e.rb1820045
title: Magnetic excitations in the half-metallic shandite Co3Sn2S2

description: Co3Sn2S2 is a metallic ferromagnet with Tc = 177 K, which crystallizes in a shandite-type structure.  Below the Curie temperature its electronic structure forms a half-metal state. Such systems attract much scientific attention due to its possible applications in spintronics. However, they are also interesting from the fundamental point of view. There are two kinds of magnetic collective excitations: transverse modes, which are described by the Heisenberg-like hamiltonian, and longitudinal modes. According to our theoretical estimations, these modes have gaps of different order in the proposed system. Previously, it was shown that the magnetism in Co3Sn2S2 can be suppressed by doping it with indium or iron, thereby initiate quantum phase transition. So, it is justified to rise a question about the role of the different kinds of magnetic excitations and how they respond on doping.
DOI: 10.5286/isis.e.rb1510057
title: Exploring the Magnetic Behaviour of New S = 1/2 Vanadium Oxyfluoride Kagome Antiferromagnets

description: Quantum spin liquid (QSL) states emerge when the arrangement of magnetic moments in a material frustrates magnetic interactions and low spin magnetic moments allow for strong quantum fluctuations. The low temperature magnetic properties of QSLs are very unusual and are not well understood. One of the best candidate materials to host a QSL ground state is a S = ½ kagome antiferromagnet, which possesses a network of corner sharing triangles of antiferromagnetically interacting S = ½ species. We propose to perform the first muon spin relaxation study of two new V4+ based S = 1/2 kagome antiferromagnets, ImVOF ([V9O6F26][C3H5N2]5) and its quinuclidinium templated analogue ([V9O6F26][C7H14N]5) on the MuSR spectrometer.
DOI: 10.5286/isis.e.rb1510166
title: Liquid-like behaviour of copper in thermoelectric tetrahedrites

description: Thermoelectric materials offer opportunities for the recovery of waste heat into useful electrical energy. As part of a nine member consortium, which included 3 SMEs and 2 large scale enterprises and was supported by the FP7 program, we have investigated the thermoelectric properties of a range of sulphides. This included phases with the tetrahedrite structure, which are promising thermoelectric materials.  Our measurements on p-type tetrahedrites indicate that these materials exhibit an unusually low thermal conductivity. In this experiment we seek to exploit neutron diffraction to investigate the mobility of the copper ions within the tetrahedrite structure as a function of temperature, its effect on the thermoelectric properties and impact on long-term stability of these phases.
DOI: 10.5286/isis.e.rb1510364
title: Spin-Luttinger Liquid phase in a model strong-rung quantum spin ladder

description: Spin ladders represent a class of low-dimensional quantum magnets that occupy a regime of subtle behaviour which lies between the stark extremes of the one-dimensional chain or two-dimensional plane. Here we propose to probe the dynamics of (Hpip)2CuCl4 using longitudinal fields to quantitatively probe the low-energy excitations of the Luttinger liquid phase on the muon time-scale. This is the first measurement of this kind on a strong-rung system and builds on the principle recently demonstrated in our measurements, made at ISIS in the last cycle, on the strong-leg spin ladder DIMPY.
DOI: 10.5286/isis.e.rb1510426
title: Dynamics of Water on Surface of Reverse Osmotic Membranes

description: We are proposing 4 days of beamtime on LET or 8 days on IRIS [using PG(004) reflection] to complete the experiment on a water/polyamide system which was started in 2013. Polyamide is a surface material of reverse osmotic membranes currently used for desalination and waste-water reclamation. The previous QENS data revealed that there are basically two kinds of relaxations; the faster one may be for ¿free¿ (but confined and not bulk) water and the slower one for polyamide and water strongly bound by polyamide. However, there are some ambiguous points owing to the limited dynamic range of IRIS PG(002). In this continuation experiment, we propose to measure relatively faster time region (1ps¿0.1ns) using LET or IRIS at PG(004) mode. These data, combined with the previous data, will enable us to analyze the dynamics of the system more precisely and comprehensively.
DOI: 10.5286/isis.e.rb1510469
title: Layered lithium iron selenide hydroxide superconductors

description: FeSe is a superconductor below 8.5 K.  Very recently, we have found superconductivity in a wide compositional range in a series of layered lithium iron selenide hydroxides.  Control of thereactions shows a correlation of the occurrence of superconductivity and increasing Tc, up to 39 K, with the minimisation of the concentration of iron vacancies in the iron selenide layer, whichsimultaneously increases the electron count on iron in the selenide layers.  This experiment will extract (a) the behaviour of the superfluid stiffness as we vary Tc controllably in this series; (b) the development of the magnetism as composition is varied.
DOI: 10.5286/isis.e.rb1510470
title: Understanding the magnetic phase diagram in capped MnSi thin films

description: Skyrmions are a topologically non-trivial magnetisation pattern that form in crystal structures whose broken inversion symmetry gives rise to the Dzyaloshinsky-Moriya interaction (DMI). Their robustness against thermal fluctuations make them ¿ in thin film form - attractive candidates for non-volatile memory devices. While bulk crystals of skyrmion materials have been well studied, the picture in thin films is still rather controversial due to added complications such as epitaxial strain, surface anisotropy, and magnetic biasing effects. We propose to use polarised neutron reflectometry to resolve the key features of the thin-film skyrmion phase diagram, investigating the twisting of magnetisation vectors that arises. In particular we hope to be able to unravel the influence of the interfaces on the magnetic state of the film in terms of their structural and magnetic effects.
DOI: 10.5286/isis.e.rb1510542
title: The structural role of Mg in enhancing the performance of P2-type Na2/3Ni1/3-xMgxMn2/3O2 cathode materials

description: Na-ion batteries have become an important area of research in the last few years. Na2/3Ni1/3Mn2/3O2 with the P2-type structure is a promising cathode in Na-ion batteries due to its high capacity and stability. However, it experiences a structural transition at high voltages (by gliding of the transition metal layers) that causes a detrimental effect on the battery life. Our studies have shown that Mg-doped Na2/3Ni1/3Mn2/3O2 materials exhibit excellent performance with capacities greater than 130 mAh g-1 that remain stable up to 20 cycles. These results contrast to the undoped materials, where a capacity loss of 43.7% is observed. We propose a 5.5 day experiment on POLARIS to deliver a model of the long-range and short-range (using PDF analysis) to understand the role of Mg on the stabilisation of these compounds and thus its performance and further optimisation.
DOI: 10.5286/isis.e.rb1510582
title: Excitations of the Zeeman ladder in a transverse field in the Ising antiferromagnetic chain compound RbCoCl3

description: The excitations of an Ising antiferromagnetic chain have been studied in the past and are known to form either continuous spectrum or Zeeman ladders. Such a system can be brought to a quantum phase transition by applying a transverse magnetic field and inducing a ferromagnetic state: however, theoretical studies suggest that when a transverse subcritical field is applied the excitations of such a system display an interesting series of splittings. Mapping the field- and temperature dependence of these modes is therefore very important to the understanding of the Ising chain in a subcritical transverse field. LET is the ideal instrument for this experiment, as its fantastic resolution, large detector capability, low backgrond and flux are required to efficiently map and resolve these excitations.
DOI: 10.5286/isis.e.rb1610026
title: Constructing analogues of gemini and oligomeric surfactants through noncovalent binding

description: Gemini-like and oligomeric-like surfactants can be constructed by single-chain or gemini surfacants with connecting molecules through noncovalent binding without complicated chemical synthesize. And these complexes behave as synthesized gemini and oligomeric surfactants in aqueous solution, exhibiting not only superior physicochemical properties but also various aggregate transitions. Various aggregates can be observed in these mixed systems including spherical micelles, vesicles and long threadlike micelles. SANS experiments would be extremely powerful to obtain the detailed structure information of the aggregates, such as precise size of core and shell, shape, aggregation number, and localization of different components, facilitating to further understand binding process and better control the formation of aggregates.